Wikipedia talk:WikiProject Mathematics/Archive/2016

Jan 2016

Which other articles should link to Generalized structure tensor?

Which other articles should link to Generalized structure tensor? Michael Hardy (talk) 18:56, 1 January 2016 (UTC)

Trisection image

I have listed at Wikipedia:Files for discussion/2016 January 1 an angle trisection image that Sunwukongmonkeygod (talk · contribs) added to angle trisection. Please contribute to the discussion there. —David Eppstein (talk) 05:54, 1 January 2016 (UTC)

When this proposed trisection technique is applied to a right angle, it yields an angle whose tangent is 1/2, where one would need an angle whose sine is 1/2. That's trivially easy to show without knowing the classic theorem that is far from trivially easy to prove. Michael Hardy (talk) 19:19, 1 January 2016 (UTC)

Wow! Boris Tsirelson (talk) 19:28, 1 January 2016 (UTC)

I believe the nominator made a mathematical mistake. If I haven't made a mistake, the construction trisects the chord, rather than the angle, making it a good approximation for small angles, although obviously not exact. I don't thinkit belongs in the article, and it certainly doesn't belong on Wikipedia under that title, but as an approximate angle trisector.

$2\arcsin {\tfrac {1}{3}}\sin {\tfrac {\theta }{2}}\neq {\tfrac {\theta }{3}},$

But it's close. — Arthur Rubin (talk) 18:02, 2 January 2016 (UTC)

Additive

My first thought when I see additive function is the article corresponding to Cauchy's functional equation; I think we need more links between the articles presently at additive function, additive map, and Cauchy's functional equation. I'd like to bring the matter up here, rather than at the article talk pages, to see if any of the expert Wikipedians with an interest in mathematics can provide some input, before making a formal proposal on the article talk page(s). — Arthur Rubin (talk) 06:30, 3 January 2016 (UTC)

Equivalence relation, equivalence class, and partition of a set

I don't want to propose it formally without input from people interested in mathematics, but not necessarily mathematicians. There is considerable overlap between those articles; equivalence relation has sections pointing to equivalence class, quotient set (which redirects to equivalence class), and partition of a set. Perhaps some merger of the articles would be appropriate, if we can avoid Marxist interpretations of class. — Arthur Rubin (talk) 06:27, 3 January 2016 (UTC)

On a priori grounds (i.e., I haven't looked at any of the articles before writing this) I would think that equivalence relation and equivalence class could be a single article. But the words "set partition" suggest a particular approach and collection of results related to the combinatorics of finite sets, and these should be in a separate article. --JBL (talk) 15:10, 3 January 2016 (UTC)

After a look at the articles, I agree with JBL. Equivalence relation and equivalence class should be merged and partition of a set should stay separate. Another thing to keep in mind is that people sometimes do want to partition sets without thinking about equivalence relations. Merging partitions of a set to equivalence relation would confuse many readers. Happy Squirrel (talk) 19:18, 3 January 2016 (UTC)

This raises the question of whether there are situations where one can have an "equivalence relation" without a notion of "equivalence class". Anyone who knows more than I do about stacks and groupoids, feel free to chime in. Sławomir
Biały 20:14, 3 January 2016 (UTC)

I believe the only thing that categories buy you in this situation is a different language (possibly less scary? or maybe more) for discussing proper classes. Ozob (talk) 23:12, 3 January 2016 (UTC)

There's also quite a bit of overlap in topic between Disjoint sets and Partition of a set. —David Eppstein (talk) 19:40, 3 January 2016 (UTC)

Semi-major axis page move proposed

Should Semi-major axis be moved to Elliptical axis? See Talk:Semi-major axis#Requested move 4 January 2016. Johnuniq (talk) 05:05, 4 January 2016 (UTC)

Draft:Microplane Model for Constitutive Laws of Materials

Hi. Could we get some input on this article over at AfC? Thanks. Onel5969 ^{TT me} 12:58, 4 January 2016 (UTC)

Proposed deletion of Degeneracy (mathematics)

The article Degeneracy (mathematics) has been proposed for deletion because of the following concern:

It lacks notability (WP:N). There is no mathematical topic of degeneracy. This article is just a small rag-bag of arbitrary and uncited examples.

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the {{proposed deletion/dated}} notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the article to address the issues raised. Removing {{proposed deletion/dated}} will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. — Cheers, Steelpillow (Talk) 14:15, 27 December 2015 (UTC)

PROD template removed. — Cheers, Steelpillow (Talk) 09:36, 31 December 2015 (UTC)

And now it's up for AfD: Wikipedia:Articles for deletion/Degeneracy (mathematics). —David Eppstein (talk) 21:22, 6 January 2016 (UTC)

spelling issue for math theorems: s's versus s'

User talk:Cherkash seems to systematically replace s' by s's in various math articles and move them as well. Affected articles are Pappus's hexagon theorem, Pappus's area theorem, Desargues's theorem, Pappus's centroid theorem. I don't really have strong opinion on the subject although to my knowledge the old spellings were correct (and used in math literature) and I'm always a bit wary about articles getting moved from correct version to another due to (individual) taste preferences.

Crudely speaking both versions seems to be correct with various spelling and grammar guides disagreeing or simply declaring it a matter of taste. In math literature both spelling can be found as well (a Google books test on Desargues'(s) theorem for instance yielded 15,800 hits for Desargues' theorem versus 24,500 hits for Desargues's theorem).

So what are the opinions here? Everbody ok with such moves?--Kmhkmh (talk) 12:01, 3 January 2016 (UTC)

Just to be clear: it's not just a matter of renaming the articles – the articles text often used both versions as well (probably reflecting the stylistic preferences of different editors at different times, although most of the entries seemed to agree with s's rather than s'). So all I did was pretty much harmonize possessives' use in the articles, and brought articles names in line with the proper usage, as showcased in the body of the articles. See also MOS:POSS.

As for the reasons the 's form is always preferable to a simple apostrophe in case of singular possessives: there are usually very limited "traditional" exceptions to the use of 's for singular possessives even when the noun ends with "s". Jesus seems to be one case where most style guides and grammar books agree on "Jesus' " as being acceptable (although Jesus's is still quite correct, Jesus' is an acceptable form). As for the rest, even if noun ends in "s", for as long as it's a singular noun, the 's should be added, not simply an apostrophe. See again MOS:POSS, as well as more detailed treatment here and here.

Also, in case of French names (like Desargues) where the ending "s" is silent (pronounced "desarg"), it's an especially compelling case since most all English speakers actually say "desargs" for the possessive, and it should be clear that this extra "s" sound comes from the proper use of 's as the singular possessive's ending. Again, per MOS:POSS, this is a more clear case where 's should be added, based on the pronunciation. cherkash (talk) 12:35, 3 January 2016 (UTC)

I agree with applying the 's to Desargues, for the stated reason. This is something that bothered me about our spelling at that article in the past. I am neutral regarding the spelling of Pappus' versus Pappus's, since the extra s is silent there. As long as the article is consistent, I don't see a problem. Sławomir
Biały 12:51, 3 January 2016 (UTC)

Actually, I don't agree that the extra s in Pappus's is silent. In my personal usage, I would be more likely to write Pappus's and pronounce it with three syllables. If I heard someone pronounce the possessive with two syllables, I would transcribe it as Pappus'. --Trovatore (talk) 19:11, 7 January 2016 (UTC)

Well while the article on Desargues's theorem did indeed have a somewhat inconsistent spelling, the theorems by Pappus did not as far as I can tell, so the claimed harmonizing argument doesn't really apply here. Also while the arguments above are correct for Desargues in particular with regard to the silent s, they don't apply to Pappus either. In fact Pappus seems exactly a case like Jesus and the linked WP article even gives fellow Greek Socrates as another example for s' case. In fact it even claims (though without citation) that the French names with a silent s can be spelled either way and gives Descartes and Dumas as examples.--Kmhkmh (talk) 13:48, 3 January 2016 (UTC)

AfC submission

See Draft:Katugampola fractional operators and Draft:Thin plate energy functional. Thank you, FoCuS contribs; talk to me! 21:08, 7 January 2016 (UTC)

• Also Draft:Learning data representations, that while not strictly mathematical, could use some experienced eyes. Best, FoCuS contribs; talk to me! 21:11, 7 January 2016 (UTC)

Are algorithms invented or discovered?

When editing a Wikipedia article are mathematical algorithms "invented", or are they "discovered"? Or maybe it doesn't matter either way? --82.132.234.81 (talk) 18:12, 7 January 2016 (UTC)

Oh! This is a special case of a famous philosophical question: do we invent or discover mathematical objects? No chance of consensus. See for instance Platonism#Modern Platonism. Boris Tsirelson (talk) 18:23, 7 January 2016 (UTC)

I agree no chance of ever settling that one in satisfactory way. In doubt just leave the choice of words here to main contributor(s) of the article in question.--Kmhkmh (talk) 01:23, 8 January 2016 (UTC)

Links to Egorychev method

Which other articles should link to Egorychev method? Michael Hardy (talk) 01:52, 8 January 2016 (UTC)

No-retraction theorem

No-retraction theorem is only indirectly mentioned in "Brouwer fixed-point theorem"; no article, not even redirect, why? Boris Tsirelson (talk) 17:52, 23 December 2015 (UTC)

Since no one else is replying, I will go out on a limb and guess it is because no one has been BOLD enough to create it. It is definately notable. Do you want to create it? Happy Squirrel (talk) 04:28, 2 January 2016 (UTC)

Rather far from my interests. I'd prefer it created by someone closer to topology than me. Someone who knows better the history of that theorem, its influence etc. Boris Tsirelson (talk) 20:04, 6 January 2016 (UTC)

A redirect, for now. Boris Tsirelson (talk) 12:45, 8 January 2016 (UTC)

Numerals vs. numeral systems

There is a discussion at Talk:Arabic numerals#Numerals and numeral systems that readers of this page might wish to join. Paul August ☎ 15:04, 10 January 2016 (UTC)

Jacobian Conjecture article

I have proposed a change to the JC article on the JC talk page in the section titled 'Symmetric Case'. I need someone to implement it who has better editing skills than I do. Thank you,

L.Andrew Campbell (talk) 02:28, 13 January 2016 (UTC)

Local cosine tree

If the new article titled Local cosine tree is worth keeping, it needs some cleanup and other work. Michael Hardy (talk) 03:50, 5 January 2016 (UTC)

It was at its foundation plagiarized from a published book, as was another recently created article by the same editor, Cohen's Class. I have deleted both articles, but if someone thinks they should be re-created using original rather than copied text I won't complain. —David Eppstein (talk) 02:39, 13 January 2016 (UTC)

Renaming Graph (mathematics)

There is a discussion here about renaming the article Graph (mathematics). There appears to be consensus in favor of a new name (at least among the small number of editors who have commented), but not about whether the target should be Graph (graph theory) or Graph (discrete mathematics). Additional input is welcome. --JBL (talk) 15:49, 13 January 2016 (UTC)

AfC help - again

Hi all. Could someone take a look at Draft:Lattice Delay Networks and offer an informed opinion as to the veracity and state of the article. Please ping me if and when you do. Thanks. Onel5969 ^{TT me} 12:57, 14 January 2016 (UTC)

Is it math? Rather, Electronic engineering. Boris Tsirelson (talk) 18:59, 14 January 2016 (UTC)

MWException in maths expression

Tracked in Phabricator
Task T121762

I noticed an internal error

[cc7bc57d] 2015-12-17 13:38:05: Fatal exception of type "MWException"

here. Not having a \binom in a \limits subscript appears to have fixed it. I assume correct LaTex would be to use something like \substack, but in any case I am a bit worried that I get thrown an exception instead of a helpful error message. Does anybody have an idea or should I post this to WP:VPT instead? —Kusma (t·c) 13:42, 17 December 2015 (UTC)

Yup, see it too, but only with MathML. The fix looks acceptable. I vaguely recall that PigTex (our "LaTeX") hates \substack. YohanN7 (talk) 13:55, 17 December 2015 (UTC)

I've added a bug report: https://phabricator.wikimedia.org/T121762. It looks like its a bug in the code so its best to go straight to the bug system rather that use VP:T. --Salix alba (talk): 14:24, 17 December 2015 (UTC)

Thank you! I also figured that reporting this is what I should do, so it is also at phab:T121763. I hope I have merged the tasks correctly. —Kusma (t·c) 14:29, 17 December 2015 (UTC)

The issue has been fully solved and everything is back to normal now :) Thank you for raising the issue. Marko Obrovac, Wikimedia Foundation (talk) 00:03, 18 December 2015 (UTC)

Now it looks like all of the vertical spacing in mathml is broken. See the screenshot of Heisenberg group. Can anyone else confirm this? I've noticed it only in Firefox. It looks normal in Chrome. Sławomir
Biały 12:18, 22 December 2015 (UTC)

@Slawekb:https://www.dropbox.com/s/eg8hj8oh0umrfck/Screenshot%202016-01-06%2019.12.13.png?dl=0 that's how it looks for me. Which FF version are you using? --Physikerwelt (talk) 18:14, 6 January 2016 (UTC)

Version 43.0.4. According to the Mozilla web site, this is the latest version. Sławomir
Biały 12:20, 15 January 2016 (UTC)

Category:Benedictine mathematicians

Category:Benedictine mathematicians, which is within the scope of this WikiProject, has been nominated for deletion. If you would like to participate in the discussion, you are invited to add your comments at the category's entry on the Categories for discussion page. Thank you. RevelationDirect (talk) 04:35, 16 January 2016 (UTC)

Prerequisite hatnotes

Re: the "incomprehensibility" problem discussed at Wikipedia:Wikipedia Signpost/2016-01-06/In the media: what would you think of putting WP:Hatnotes at the top of technical articles, along the lines of

To fully understand this article, an understanding of measures, rings, and σ-algebras is recommended.

I would find this very helpful. I often go to look up a math topic I've heard of, and wade through several paragraphs before I realize how badly unprepared I am (I'm a first-year undergraduate). Math gives very little context besides the definition; it's much easier for a nonspecialist to understand what Battle of Towton is about than Carathéodory's extension theorem. Math books list prerequisites in Chapter 0, but Wikipedia has no Chapter 0, so it's easy to get out of one's depth with no idea how to retreat. There might be OR concerns, but I think it would usually be fairly obvious. FourViolas (talk) 22:53, 7 January 2016 (UTC)

This is in the FAQs: Any article with this problem could be written better by weaving its prerequisites into its exposition. Sadly, we have far too many poorly written articles. If you can point out particular articles, then I'm sure you can find interested editors to help you improve them. Ozob (talk) 00:30, 8 January 2016 (UTC)

I agree it's in the FAQ. The example of Reproducing kernel Hilbert space is rather funny. I assume it would never occur to a reader of that article that they would first need to know what a Hilbert space is. How is this any different from an article like Microcell-mediated chromosome transfer, where one needs to know what a cell is, what a chromosome is, etc.? One can get most "prerequisites" just by following links. There's no need to bash readers over the head with this. If a reader isn't intelligent enough to figure this out, chances are they wouldn't get much out of the article Reproducing kernel Hilbert space regardless of what kinds of hatnotes we chose to decorate it with. Sławomir
Biały 21:25, 20 January 2016 (UTC)

For many articles simple honesty would require that one should say "an understanding of WHATEVER is needed" rather than "...is recommended". Michael Hardy (talk) 19:52, 20 January 2016 (UTC)

A quote from the Signpost article linked in the beginning of this discussion (see "Reproducing kernel (impenetrable science)" there):

Indeed, you have to know what is a vector space, then an Hilbert space, then a linear kernel before to understand the circumstances that allows an Hilbert space to possess a kernel that has the reproducing property. This is not a cabal to intimidate anyone, this is the fact that floor and walls should precede roof. Maybe this constraint is the reason why there are not only books, but also teachers and Universities. What a marvelous discovery! Pldx1 (talk) 09:28, 7 January 2016 (UTC)

Boris Tsirelson (talk) 21:03, 20 January 2016 (UTC)

Thoughts on an edit

Thoughts on this edit to Geodesic are welcome. I've started a discussion on the talk page. Sławomir
Biały 15:30, 23 January 2016 (UTC)

D. D. Wall's open question

I think this Wall-Sun-Sun article section for the existence of such primes, could be a little more balanced to mention Wall's original hypothesis of non-existence, and consequently his open question that these primes may, or may not exist after all.

Let $F_{u_{p^{1}}}$, be the smallest Fibonacci number divisible by the prime $p$.

Let $F_{u_{p^{2}}}$, be the smallest Fibonacci number divisible by $p^{2}$.

Let $\prod _{1}^{n\geq 1}$ be the quotient of primitive(characteristic) prime factor(s), ie factors that have not occurred in any earlier Fibonacci numbers.

$\left\lbrace {n\mid m}\ {\text{iff}}\ {F_{n}\mid F_{m}}\right\rbrace \,n\geq 3$

$p^{2}\mid F_{u_{p^{1}}}\ {\text{iff}}\ F_{p^{2}}\mid F_{F_{u_{p^{1}}}}$

If an integer $i$, has prime factorization, $p_{1}^{e_{1}}\cdot \ p_{2}^{e_{2}}...p_{n}^{e_{n}}$ then the entry point of $i$ equals, $\left\lbrace u_{i}=\operatorname {lcm} ({u_{p_{1}^{e_{1}}},u_{p_{2}^{e_{2}}},...u_{p_{n}^{e_{n}}}})\right\rbrace$.

${\text{If}}\ i=F_{F_{u_{p^{1}}}}\ {\text{then}}\ F_{p^{2}}\nmid \!F_{F_{u_{p^{1}}}}\ \left\lbrace F_{F_{u_{p^{1}}}}\neq F_{F_{u_{p^{2}}}}\right\rbrace$.

${\text{Abstract example, }}p_{1}=p,\ e_{1}\geq 2$

${\text{If }}i=(F_{p_{1}^{2}}\ \cdot \ F_{p_{2}^{e_{2}}}\ \cdot \ ...\ F_{p_{n}^{e_{n}}}\ \cdot \ \prod {})=F_{F_{u_{p^{1}}}}\ {\text{then does i's entry point }}u_{(F_{F_{u_{p^{1}}}})}=F_{u_{p^{1}}}\ {\text{still?}}$

${\text{No, since any extra powers of p produce a later entry point, }}u_{i}=\operatorname {lcm} (p_{1}^{2},\ p_{2}^{e_{2}},\ ...\ p_{n}^{e_{n}},\ F_{u_{p^{1}}})\neq F_{u_{p^{1}}}=F_{pu_{p^{1}}}.$

${\text{While the factor, }}j=(F_{p_{1}^{1}}\ \cdot \ F_{p_{2}^{e_{2}}}\ \cdot \ ...\ F_{p_{n}^{e_{n}}}\ \cdot \ \prod {}){\text{ always has an entry point of, }}u_{j}=\operatorname {lcm} (p_{1}^{1},\ p_{2}^{e_{2}},\ ...\ p_{n}^{e_{n}},\ F_{u_{p^{1}}})=F_{u_{p^{1}}}.$

${F_{u_{p^{1}}}}\neq {F_{u_{p^{2}}}}$

${u_{p^{1}}}\neq {u_{p^{2}}}$

${u_{p^{2}}}={pu_{p^{1}}}$

$p^{2}\nmid \!F_{u_{p^{1}}}$

References

Preceding post either is a copy or is very similar to the post by the same author at Talk:Wall–Sun–Sun prime#Existence, and the first sentence refers apparently to Wall–Sun–Sun prime#Existence. D.Lazard (talk) 20:39, 25 December 2015 (UTC)

One should not write this:

$p^{2}|F_{u_{p^{1}}}\,$

but rather this:

$p^{2}\mid F_{u_{p^{1}}}\,$

Likewise "lcm" should use \operatorname{lcm}, and it is horribly vulgar to use an asterisk for ordinary multiplication in a TeX-like setting. Michael Hardy (talk) 20:52, 27 December 2015 (UTC)

Thank you.Primedivine (talk) 03:47, 28 December 2015 (UTC)

This section starts by saying this:

I think this article section could be

WHICH section of WHICH article?? Michael Hardy (talk) 20:37, 29 December 2015 (UTC)

The Wall-Sun-Sun article section for the existence of such primes. I edited it above.

Perhaps the consensus is leaning toward Wall-Sun-Sun primes existing. May I ask if there is any problem with the restatement of D. Wells form, ie

$F_{n}\mid F_{m}\ {\text{iff}}\ n\mid m,n\geq 3$

Is this statement equivalent and true?

$n\mid m\ {\text{iff}}\ F_{n}\mid F_{m},n\geq 3$

Considering, $n=p^{2},m=F_{u_{p^{1}}}$ as indices.

The integer $F_{F_{u_{p^{1}}}}$ is to be divisible by $F_{p^{2}}$, and $F_{p}$ correct? Primedivine (talk) 23:43, 29 December 2015 (UTC)

Please take a look at the conclusion of Zhi-Zong-Sun and Zhi-Wei-Sun's paper, pages 386+. It states what I've stated above, although less elegantly. Why, has everyone overlooked this part of their paper?

Sun-Sun

Z. H. Sun and Z. W. Sun, Fibonacci numbers and Fermat's last theorem, Acta Arithmetica, Vol. 60, No. 4 (1992), 371-388

I suggest that we come up with an update for the article, that is balanced to reflect this previously unrecognized viewpoint, ie $p\mid \mid F_{u_{p^{1}}}$, where $\mid \mid$ means exactly divides, $u_{p^{1}}\neq u_{p^{2}}$.Primedivine (talk) 18:37, 3 January 2016 (UTC)

If it is truly a "previously unrecognized viewpoint", then Wikipedia is not the place to publish it. Indeed, presumably you should be able to write something up and submit it for peer review if you feel strongly about it. Sławomir
Biały 19:06, 3 January 2016 (UTC)

I meant previously unrecognized by editors, not unrecognized by reliable sources. Primedivine (talk) 20:53, 3 January 2016 (UTC)

EDIT The abstract example above clarifies the proof by contradiction. The problem named as, "The non-existence of Wall–Sun–Sun primes", as shown at OEIS. I have seen this referenced in several papers, where the original viewpoint or consensus was that they do not exist. Primedivine (talk) 14:47, 24 January 2016 (UTC)

Nose-following and hand-waving

I've been working a lot today on the Hand-waving article (which is much broader and more general than just the maths usage, and also includes, barely, nose-following). I'm having difficulty finding a clear definition of nose-following in a RS. The best I can come up with (as I used at the Follow one's nose disambiguation page) "a mathematics publishing and pedagogical term meaning to pursue a mathematical solution by mechanistically applying one's already-understood concepts without learning or applying anything new". I'm not certain this is properly nuanced (especially since I ran into two seemingly positive uses: "the ... enlightened nose-following that mark mathematical exploration" and "they did not yet know the 'follow your nose' proof tactic which I learned in my first upper division math class in college", plus contextually neutral ones like "The thing about nose-following proofs is that they are not very interesting. They need to be taught to students, of course" and "A student needs a tremendous amount of experience before they are ready to do math by simply following their nose."), and I'd like to have a source before putting it in the article (all these come from blogs and forums). Worse, the article says nose-following is the opposite of hand-waving, but what I've been able to glean of the meaning of nose-following, the two concepts are totally tangential, and certainly not antonyms. This suggests either our article is saying something wrong, a bunch of people are wrong on the Internet (I know that's hard to believe), or I have way too little information to grok with fullness what "opposite" relationship is meant.

That maths section at the article badly needs work. After I reworked a lot of it, I discovered the entire thing was copy-pasted from a Quora post, making it both OR and COPYVIO. Maybe enough of it's been altered by subsequent edits to not be a copyvio (and the Q poster's name is very familiar, so he might be 'a Pedian who wouldn't object anyway), but it looks to me like a lot of the assertions are opinional, and one was already flagged as iffy.

Also, the term "nose proofs" sometimes hyphenated at "nose-proofs" (plus "nose-proofing", etc.) appear to be directly related and should be covered in the same section.  — SMcCandlish ☺ ☏ ¢ ≽^ʌⱷ҅_ᴥⱷ^ʌ≼  14:20, 26 January 2016 (UTC)

I read an article recently by Raoul Bott who said Rene Thom was apparently famous for "[doing] mathematics with his fingers and his hands". Quoting Bott (1988) "Morse theory indomitable", Publ IHES, 68:99-114:

"I still recall the motions of his hands as he taught me that for manifolds with boundary, only half of the critical points of the boundary really 'counted'."

It's curious that Bott appears to mean the metaphor both in its colloquial sense (of our article), and in the literal sense. Later on, he says:

"At infinity, his hands and fingers seemed to take over."

I'm not sure this worth adding to the article, but I found Bott's candid descriptions of Thom to be rather beautiful. Sławomir
Biały 14:26, 26 January 2016 (UTC)

History of numbers

History of numbers is currently almost the most vacuous article that can be imagined. Michael Hardy (talk) 03:16, 25 January 2016 (UTC)

I'm sure a more vacuous article can be imagined, although, I admit, I've never seen one. — Arthur Rubin (talk) 17:24, 26 January 2016 (UTC)

Trillium theorem

"Trillium theorem" (scalene version)

What should become of the article titled Trillium theorem? Deletion is proposed on the ground that no theorem by that name can be found in the Civilized part of the Universe, but might it be known by some other name and otherwise worthy of inclusion? Michael Hardy (talk) 01:45, 25 January 2016 (UTC)

I think it's fairly clear. It depends on what references are found. If the result can be sourced, and it can be established that trillium theorem is the standard name, then it should be kept (or possibly merged somewhere). If the result can be sourced, but not under that name, then it should be given the standard name, if there is one, or possibly merged somewhere. If the result cannot be sourced, then the article should be deleted without prejudice to recreation with good sources. --Trovatore (talk) 02:10, 25 January 2016 (UTC)

It might be a good idea to search for the Russian name in the article. Perhaps google.ru? — Arthur Rubin (talk) 03:38, 25 January 2016 (UTC)

The theorem looks vaguely like something I saw at the Intel Science and Engineering Faire last spring, from a Russian student. — Arthur Rubin (talk) 03:41, 25 January 2016 (UTC)

I asked about this over on my Google+ account and got a link to a document in Russian that looks relevant: http://www.geometry.ru/persons/kushnir/9pointcircle.pdf — I don't read Russian but if someone else does and can use it to source this article, please do. I also got a response from a Polish mathematician who writes that this is indeed well-known folklore, especially in Olympiad circles, and that the "trillium theorem" name (in its Polish form) is uncommon but not unknown. —David Eppstein (talk) 00:33, 26 January 2016 (UTC)

In case that it is simply one of those "well known but unnamed theorems" and no appropriate Russian source can be found there is also the option of moving its content to another article (like circumcircle or triangle) before deleting it.--Kmhkmh (talk) 00:52, 26 January 2016 (UTC)

The picture which goes with the article is potentially misleading because in it the given triangle appears to be isosceles rather than a general scalene triangle. Consequently, the midpoint of AC, the intersection of AC with BI, and the point where AC is tangent to the inscribed circle all appear to be the same point which they should not be. JRSpriggs (talk) 01:37, 26 January 2016 (UTC)

Well that can be quickly fix with a replacement drawing assuming we keep the content.--Kmhkmh (talk) 15:22, 26 January 2016 (UTC)

I switched the article to use Kmhkmh's drawing. Thanks! —David Eppstein (talk) 17:07, 26 January 2016 (UTC)

If "trillium" is rare even in Polish, perhaps we should use a (literal) translation of the best Polish (or Russian) name. In the absence of that, we should use MathWorld's made-up name, or perhaps make up our own. I think "trident" would be the best choice, rather than naming it after a local (to the source of the theorem) three-lobed plant. — Arthur Rubin (talk) 16:51, 26 January 2016 (UTC)

It's called the "trident theorem" on p.8 of http://spotidoc.com/doc/1237477/xi-geometrical-olympiad-in-honour-of-ifsharygin-the — I'm not sure whether that counts as a reliable source. —David Eppstein (talk) 19:15, 26 January 2016 (UTC)

That is strictly speaking a slightly different theorem as it uses the perpendicular bisector (of a side) rather than the angle bisector. However the angle bisector and the perpendicular bisector of the opposing side do intersects the circumcircle in the same point thus yirld the same conclusion.--Kmhkmh (talk) 20:26, 26 January 2016 (UTC)

It looks vaguely like the polar of the 9-point circle. The Russian article pointed to above is titled "9-point circle", and seems to be about the 9-point circle. — Arthur Rubin (talk) 17:14, 26 January 2016 (UTC)

Does Mathworld have theorem with a name attached to it? If that is the case I'd see that as a sufficient source for now and to close the deletion request.--Kmhkmh (talk) 17:51, 26 January 2016 (UTC)

I don't know if this helps the discussion or not, but I have found the result (without a name) written as the justification of a construction problem in Aref and Wernick's Problems and Solutions in Euclidean Geometry, Dover, 1968, page 68. The problem was to construct a triangle given a vertex, the circumcircle and the center of the incircle. Bill Cherowitzo (talk) 18:29, 26 January 2016 (UTC)

The article mentioned above actually contains the result on page 34 under name 'Теорема трилистника'. Added it and two more Russian sources. Stannic (talk) 03:47, 27 January 2016 (UTC)

I'd just like to make a couple points:

1. If it doesn't have a standard name, we can't give it a name. I don't agree with Arthur's idea of making up our own. Creating neologisms is a fun game, but Wikipedia makes it too easy and takes all the sport out of it, so it has to be disallowed for that purpose.
2. Mathworld doesn't count. Mathworld loves to make up names, but unless these gain actual traction in the wider community, we shouldn't copy them.
3. Even if there's no standard name, that doesn't mean the content shouldn't stay, but it does mean it probably shouldn't have a standalone article. Actually I think that's true anyway. This is a non-obvious result, but it's also not obvious that it's very important. If there's no obvious place to merge it, then maybe someone can make a "list"-type page for little geometric facts like this (assuming it's true, which I haven't checked, but no one seems to have raised any doubts).
4. If we're keeping the content, then we don't want to delete trillium theorem; it should be made a redirect, so as to preserve the history. I don't think there's anything else by that name, so the redirect is harmless. --Trovatore (talk) 22:23, 26 January 2016 (UTC)

I've added some sources but none give it a name as a theorem. I suggest moving to Incenter–excenter circle following MathWorld [1] as this at least gets two (low quality) hits in Google scholar. Spinning the article to be more about the circle and less about the theorem shouldn't be difficult. —David Eppstein (talk) 00:53, 27 January 2016 (UTC)

incenter excenter

Some general comments:

• I agree with Trovatore that we cannot make up names for theorem on our own as that would be a violation WP:OR (names can be seen as a special of external facts, hence the name need to exist in an (published) external source. One (accepted) workaround or exception here would be to pick a purely descriptive name (that approach is often used for important current events having no established name yet). Another one might be to pick the original foreign name (assuming a foreign source for it exists) or maybe a literal translation of it.
• I disagree with Trovatore however that we can't use a name from Mathworld. Yes, WP cannot neologisms on its own because of the WP:OR aspect and of course if would highly problematic anyway if we start to establish names for the mathematical community, but we can however use or report "neologism" published on other sources. Mathworld can after all be seen as a published source and whether we personally like or not a name in Mathworld has in doubt more impact than a name that shows up in 1 or 2 rarely read mathbooks. We do usually accept the latter (absent of better sources for a name), so I see no reason not accept Mathworld here.
• I disagree with Trovatore as well with regards to the redirect. Redirects are usually used for established alternative names and should be mentioned explicitly in the target article (otherwise the purpose of the redirect is unclear to the reader). If we conclude however that there is no established name, then is exactly what we can't do and we would need to delete the entry without redirect.
• If we go for the suggested incenter-excenter circle approach we may have to drop the other language WPs as they are clearly about the theorem and not that circle. Going this way is imho basically a variation of deleting the original entry but saving its content by moving to a different entry where the content can seen be seen as appropriate and just not having its own article. We'd also a slightly different drawing bring the excenter into the picture. I provided one above, that could be used.

--Kmhkmh (talk) 03:23, 27 January 2016 (UTC)

Um, no, we can't use a neologism just because somebody uses it. We can report that Mathworld uses it, but we should not follow Mathworld, which is an utterly terrible source for names. Really really really bad. Just never never never follow Mathworld for names, ever. --Trovatore (talk) 04:07, 27 January 2016 (UTC)

On the redirect question, we can and do have redirects from all sorts of problematic names, even ones that are seriously POV. As long as they're unambiguous, there's not too much of a problem. --Trovatore (talk) 04:10, 27 January 2016 (UTC)

I'm aware of your utter dislike of Mathworld, I don't quite share it though. Mathworld does more or less fulfill the formal criteria we require from an external source (not to mention that we use it all over WP for more than a decade anyhow).

Yes, we have redirects for all sort of problematic or inofficial names, they are however (at least to my knowledge) usually established in the sense that they are used in external sources. And unless it is directly obvious from the name they are usually mentioned explicitly in the target article, because otherwise the reader doesn't understand why and for what exactly he got redirected.

--Kmhkmh (talk) 04:17, 27 January 2016 (UTC)

My dislike of Mathworld is mostly about naming. The math itself is usually fine. But Mathworld uncritically gives names that do not have any actual currency in the mathematical community. We ought to base our names on currency in the community, not the formal point that it can be found in a published source. (Especially a tertiary source.)

The point about giving notice to users as to how they arrived at a given article is a good one, albeit its importance is proportional to the chance that they would enter that search term in the first place, which I suspect is fairly low for this term. However, in any case, we can certainly report the name that Mathworld gives it. I don't object to that. That isn't a use; it's a mention. We shouldn't use the name. --Trovatore (talk) 04:26, 27 January 2016 (UTC)

History of numbers

Suppose the article titled Giraffe began like this:

well Basicly, a girrafFe is a term used by zoolooloogists to refer to when an animal has a long neck living in the planes of eastern and Southern Africa, which eats leafs.

That is the level at which the article titled History of numbers currently stands. Michael Hardy (talk) 19:04, 26 January 2016 (UTC)

. . . and now I've brought the article to a slightly less uncivilized level. Michael Hardy (talk) 22:29, 26 January 2016 (UTC)

lmao 137.124.161.12 (talk) 23:53, 28 January 2016 (UTC)

Feb 2016

Asking for suggestions

Sorry for asking something that's not really related to Wikipedia, but here goes. I recently put on line a paper I wrote commenting on the attempt of Louis de Branges de Bourcia to prove the Riemann Hypothesis. How can I bring it to the attention of those who would be interested? Eric Kvaalen (talk) 09:08, 2 February 2016 (UTC)

Why not put it on the arXiv? I did once something similar [2]. Boris Tsirelson (talk) 09:38, 2 February 2016 (UTC)

RfC of interest

Please offer comments at Wikipedia talk:Special:Preferences#RfC: Change Default Math Appearance Setting to MathML. --Sammy1339 (talk) 19:54, 2 February 2016 (UTC)

AfC help again

Hi everyone. Can we get some eyes to take a look at Draft:Extended mathematical Programming (EMP)? Comments and thoughts will be greatly appreciated. Thanks in advance for your help. Onel5969 ^{TT me} 12:55, 4 February 2016 (UTC)

Draft:Robust fuzzy programming

This draft is stalled at AFC because regular reviewers are unable to evaluate the validity of the subject as an acceptable article topic, please help. Roger (Dodger67) (talk) 10:19, 5 February 2016 (UTC)

It looks like all the sources are primary research papers by a single author/research group. This is not enough to show WP:N. I've tried to declined it, but may have messed up as its hard to do without the helper script. --Salix alba (talk): 19:06, 5 February 2016 (UTC)

Global Digital Mathematics Library

I'm currently attending this workshop which is charged with producing a white paper on how to make (or the prospects for making) progress towards a library of mathematics suited to today's digital world. As there are already a number of candidate languages in current use there are questions of who such a GDML is for, how compatible or intertranslatable the extent candidates are, whether the initial focus should be at the level of vocabulary, syntax, ambiguity (in either vocabulary or syntax), functions, concepts, or semantics, and like questions.

Are there members of WikiProject Mathematics who feel they could usefully represent the wikiproject's (or more generally Wikipedia's) attitudes towards, and opinions about, GDML's goals, prospects, methodology, etc.? Vaughan Pratt (talk) 20:36, 5 February 2016 (UTC)

When discussing semantics and ontologies, especially upper ontologies, it is very easy to fall into the trap of endlessly discussing abstract systems of classification, and formal languages for talking about mathematics. For all the tremendous amount of work that has gone into the semantic web, for instance, there is no one ontology that is universally accepted.

In this context, I think the most useful thing a Wikipedia approach can bring to this project is to urge the group to be relentlessly practical. There already exist practical ontologies on which to hang mathematical knowledge: for example, the Mathematics Subject Classification scheme and Wikipedia's own set of categorical classifications for mathematical topics. These should be built on, rather than a new ontology created ab initio. The other fundamental practicality is that any knowledge incorporated into the GDML must be easily verifiable. This is especially true if some sort of machine learning automatic summarization is going to be attempted. Neutrality would be good, too, but is perhaps too ambitious at the outset. My two cents, --Mark viking (talk) 19:58, 6 February 2016 (UTC)

Matrix_calculus#Scalar-by-matrix_identities

Hello there. Recently I am reading matrix calculus and there is one scalar-by-matrix identity that I could not understand.

According to my understanding and nominator layout, it should be ${\partial {\text{tr}}{\big (}\mathbf {X} ^{-1}\mathbf {A} {\big )} \over \partial \mathbf {X} }=-\mathbf {X} ^{-1}\mathbf {AX} ^{-1}$ while the wiki page suggests that it should be $-{\big (}\mathbf {X} ^{-1}{\big )}^{\mathrm {T} }\mathbf {A} {\big (}\mathbf {X} ^{-1}{\big )}^{\mathrm {T} }$ instead. There is no such identity in the matrix cookbook (perhaps we can replace the matrix A with I in derivative #124?), so I seek your advice.Estorva (talk) 14:04, 5 February 2016 (UTC)

I am not acquainted with "nominator layout", but according to my understanding, the differential of ${\text{tr}}{\big (}\mathbf {X} ^{-1}\mathbf {A} {\big )}$ is $-{\text{tr}}{\big (}\mathbf {X} ^{-1}\mathbf {A} \mathbf {X} ^{-1}d\mathbf {X} {\big )}$. Boris Tsirelson (talk) 19:29, 5 February 2016 (UTC)

Well, after reading that article about "nominator layout" for scalar-by-matrix derivatives I believe that it means $dy={\text{tr}}{\Big (}{\partial y \over \partial \mathbf {X} }d\mathbf {X} {\Big )}$; and if so, then $-\mathbf {X} ^{-1}\mathbf {AX} ^{-1}$, indeed. Boris Tsirelson (talk) 19:48, 5 February 2016 (UTC)

@Estirva and @Tsirel: You deficiency of TeX skills is showing. Here's a comment I just left on the talk page of the article discussed here:

When one writes {\rm tr} in TeX one does not get proper spacing before and after "tr". Thus

$a{\rm {tr}}B\,$ is coded as a {\rm tr} B, and

$a\operatorname {tr} B\,$ is coded as a \operatorname{tr} B, and

$a\operatorname {tr} (B)\,$ is coded as a \operatorname{tr} (B).

Writing \operatorname{tr} results in a certain amount of space before and after tr, and there is less space when (round brackets) follow tr than when they don't. The form {\rm tr}, on the other hand, involves no spacing conventions. The form \operatorname{tr} is standard usage and I edited accordingly.

The same thing applies to \text{tr}, which both of you used here. Michael Hardy (talk) 21:31, 7 February 2016 (UTC)

Surely I use "operatorname" (if not "DeclareMathOperator") when TeXing my articles, lecture notes etc. But this is not article, just discussion, and I did copy-paste from Estorva (who in turn did copy-paste from the article, as you alreardy know). Boris Tsirelson (talk) 06:18, 8 February 2016 (UTC)

But some people get their ideas of how to code these things by looking at stuff like this. Michael Hardy (talk) 19:56, 8 February 2016 (UTC)

That's true, but I support a relaxed attitude to talk pages. Let's not make editing Wikipedia a job. Let's not let perfect become the enemy of good. Cheers. Mgnbar (talk) 21:37, 8 February 2016 (UTC)

And let us avoid biting the newcomers (by such words as "your deficiency of TeX skills"); save this for us seniors. Estorva is here from Feb 5, 2016. Boris Tsirelson (talk) 21:45, 8 February 2016 (UTC)

Feynman dagger in PigTeX

Both variants,

$(i\nabla \!\!\!\!/'-m)S_{F}(x',x)=I_{4}\delta ^{4}(x'-x),$

$(i\not \nabla '-m)S_{F}(x',x)=I_{4}\delta ^{4}(x'-x),$

(from propagator and history) are bad. In the first, the prime is misplaced. In the second, the dagger fails to penetrate its victim and there is an ugly gap between the i and the del operator. Does anyone know of a workaround (or even a supported feature)? YohanN7 (talk) 10:05, 4 February 2016 (UTC)

For Feynman slash notation, I would put the prime after the nabla, before the shifted slash, as in

$(i\nabla '\!\!\!\!\!/-m)S_{F}(x',x)=I_{4}\delta ^{4}(x'-x),$

--Mark viking (talk) 10:55, 4 February 2016 (UTC)

Thank you. I though I tried that, but must have messed up. YohanN7 (talk) 11:20, 4 February 2016 (UTC)

That looks OK for me in PNG, but terrible in MathML (the slash is almost invisible there). —Kusma (t·c) 12:52, 4 February 2016 (UTC)

Wow, in MathML all are unacceptable. YohanN7 (talk) 13:01, 4 February 2016 (UTC)

For me the first one has the best slash. How about using that but spacing the prime a little farther,

$(i\nabla \!\!\!\!/\,'-m)S_{F}(x',x)=I_{4}\delta ^{4}(x'-x),$

—David Eppstein (talk) 21:48, 8 February 2016 (UTC)

Mathematician needed

Here: Talk:Wave function#Revision 2016-02-08 YohanN7 (talk) 13:44, 8 February 2016 (UTC)

I, for one, am already there.   :-)   Boris Tsirelson (talk) 15:33, 8 February 2016 (UTC)

No, I am not. There, editors ask simple but somewhat special mathematical questions (about vectors and operators in a Hilbert space) and accepts answers only in the form of a reliable source that treats literally the given question; any combination of two (or more) sources is rejected as OriginalResearchBySynthesis. Is there a mathematician able to satisfy them? If you are, please help them. Boris Tsirelson (talk) 11:03, 10 February 2016 (UTC)

I think that that is a bit unfair. I am personally perfectly happy with your replies. No complaints on my part. YohanN7 (talk) 12:08, 10 February 2016 (UTC)

Spacetime triangle diagram technique

I'm wondering if Spacetime triangle diagram technique should be moved either to Spacetime triangle diagram or to Spacetime triangle? (I found the article full of crude solecisms, some of which I cleaned up, and bizarrely over-complicated TeX code written by a psychotic (which probably means it was written by some software package of the kind used by people who don't know TeX code) and I cleaned up some of that too.) Ceteris paribus, I think shorter titles are better, partly because they're more likely to be found by using the search box. Michael Hardy (talk) 19:58, 16 February 2016 (UTC)

Special purpose account

The user, Ryanexler is planting a reference in various articles. He/she (most likely to be Jakob Schwichtenberg ) has done this once before (last year) and was then reverted by me. I don't feel like being this mans nemesis around here. Someone else should have a look. YohanN7 (talk) 12:30, 12 February 2016 (UTC)

Others did revert, but he is at it again. YohanN7 (talk) 10:29, 16 February 2016 (UTC)

I've warned the user about WP:REFSPAM. --Kinu ^t/_c 20:13, 16 February 2016 (UTC)

This proposed change in the title of an article might perhaps benefit from more eyeballs.

This proposed change in the title of an article might perhaps benefit from insights of participants in this page. Michael Hardy (talk) 20:21, 16 February 2016 (UTC)

Georg Cantor's first set theory article

We have a new article titled Georg Cantor's first set theory article, written largely by an expert on the history of the matter, R. J. Gray, who has published refereed papers on the topic.

I have added a "mergefrom" tag to it, which may be controversial. There is a large overlap between the two articles. The rationale for creating a separate article with a separate title is explained by R. J. Gray in this section of my user talk page.

Currently no other articles link to this new article. So that's something to work on. Michael Hardy (talk) 03:27, 13 February 2016 (UTC)

It strikes me that the article might better be titled "On a Property of the Collection of All Real Algebraic Numbers" after the title of Cantor's article. Or perhaps it should be named "Ueber eine Eigenschaft des Inbegriffes aller reellen algebraischen Zahlen" after the original title. It's a very nice article. Ozob (talk) 04:03, 13 February 2016 (UTC)

I already made that comment at the article's talk page. --Trovatore (talk) 04:06, 13 February 2016 (UTC)

Update: I made it a formal requested move. --Trovatore (talk) 20:26, 13 February 2016 (UTC)

I would say this article is a good candidate for Good article/Featured Article status, if anyone want to guide it through the process.--Salix alba (talk): 00:18, 17 February 2016 (UTC)

See Talk:Cantor's first uncountability proof/GA1 for a previous review (that led to the restructuring that created the present article). If someone does want to take it to GA, it would be a good idea to make sure the issues found there have all been taken care of. —David Eppstein (talk) 01:19, 17 February 2016 (UTC)

Copyvio

The article Effect algebra was copied from http://arxiv.org/pdf/1602.00567v1.pdf, making it a copyright violation. GeoffreyT2000 (talk) 01:49, 17 February 2016 (UTC)

Good catch. I think the copy was done in good faith; the whole text was put in a blockquote. It may be too extensive for fair use. I put up a {{copypaste}} notice on the article to encourage a rewrite. --Mark viking (talk) 04:20, 17 February 2016 (UTC)

Thanks to both of you for bringing this to my attention! Yes, I had indeed thought blockquoting the text, which is only a small section of the paper I copied it from, would constitute 'fair use'. Further, I couldn't think of how to rephrase it in my own words, given it's mostly technical definitions that I felt I could only make small changes to the wording of - which would then constitute plagiarism. This then brought me back to simply blockquoting. But having now read Wikipedia:Copying text from other sources, and that I don't know how to rewrite the text in a non-plagiarising way, I will accept the article in its current form simply being deleted. Sorry for my mistake! --Thoughtactivist (talk) 05:50, 17 February 2016 (UTC)

It would be easy enough to rewrite the definitions so they are not copyvios; I can try later this afternoon, perhaps. More important (from the editorial point of view) would be to add a few sentences saying why anyone would care about these things. @Thoughtactivist:, can you do that? --JBL (talk) 14:40, 17 February 2016 (UTC)

I've done some editing on this article. If it was a copyright violation earlier, it probably is not now. It didn't have a proper introductory sentence; I've added that. Michael Hardy (talk) 18:48, 17 February 2016 (UTC)

Well, but is it notable? Boris Tsirelson (talk) 19:46, 17 February 2016 (UTC)

Its a good question. There is an nLab page on them with a number of references. Probably mostly of interest to quantum mechanics or C*-algebra folk. --Mark viking (talk) 21:43, 17 February 2016 (UTC)

Editing help needed

Recap: I am blind and a newbie, but an expert on the Jacobian Conjecture(JC). Around January 20, I proposed a change to the JC article on the talk JC page, under the title Symmetric Case. I pointed to it here, but the pointer was archived with no action. Needs a reference to two papers by the same two authors in the same year. Please help.

L.Andrew Campbell (talk) 01:38, 18 February 2016 (UTC)

Probably you mean these:

de Bondt, Michiel; van den Essen, Arno. The Jacobian conjecture for symmetric Druzkowski mappings. Ann. Polon. Math. 86 (2005), no. 1, 43--46. MR2183036 (2006i:14069)

P.K. Adjamagbo and A. van den Essen (2007) and Alexei Belov-Kanel and Maxim Kontsevich (2007) showed that the Jacobian conjecture is equivalent to the Dixmier conjecture.

Boris Tsirelson (talk) 12:25, 18 February 2016 (UTC)

New article

I have created the System U article and would appreciate if somebody checked its wikiness. Also, looking at related articles, I noticed they have this WikiProject's rating template on their talk pages. I don't know what the process around these is, but this article should probably have one as well. —Matěj Grabovský (talk) 12:37, 19 February 2016 (UTC)

Thanks for your contribution! This looks like a well-formatted start-class article to me and I've added the wikiproject template. As a layman in this field, I don't understand the notation in your formal definition section. You might add a few words of explanation. --Mark viking (talk) 13:51, 19 February 2016 (UTC)

Thanks. I'll try to add an intuitive interpretation of the symbols. —Matěj Grabovský (talk) 15:02, 19 February 2016 (UTC)

Thanks for adding the explanatory prose. That makes it much clearer. --Mark viking (talk) 01:17, 21 February 2016 (UTC)

P-value fallacy for DYK

I'd like to get P-value fallacy in WP:DYK. (User:Sunrise gets all the credit, not me.) It'd be nice to have a decent mathematics article on the Main Page. I'd appreciate it if a few stats people looked it over and/or suggested a good "hook" for it. Realistically speaking, we probably can't expect to find very many stats people among the DYK reviewers, so I'm asking here. If anyone has comments, please be bold, or leave notes on the article's talk page. WhatamIdoing (talk) 01:56, 22 February 2016 (UTC)

List of sieve methods

In this section I found only two sieve methods listed, not including the sieve of Eratosthenes about which everyone learns in elementary school, and which is in fact the only one that I know anything about. I added several more. Quite possibly the section needs more work. Maybe even subsections on different kinds of sieves? Or maybe not? Michael Hardy (talk) 18:43, 25 February 2016 (UTC)

Tech Talk on Zotero and citations

Some of you may be interested in this:

There is a Tech Talk next Monday, 29 February at 20:00 UTC (12 Noon Pacific Time) about Zotero and the mw:citoid service.

The main subject is how to extract accurate, automated bibliographic citations from websites. This talk is mostly about Zotero, which is a free and open-source citation management tool. Zotero is used on the Wikipedias through the automagic citoid service. Citoid is currently an option in the visual editor and will (eventually) be used for automated citations in the wikitext editor at some Wikipedias. Zotero is also used by many academics and researchers, and most of the information presented will be useful to people outside of Wikipedia as well.

Please share this invitation with anyone that you believe will be interested. If you have questions, then please leave a note on my talk page. Whatamidoing (WMF) (talk) 03:43, 24 February 2016 (UTC)

Would this be a related question?: Do page numbers in references cited in Wikipedia obey Benford's law? Gathering data to examine this would be quite onerous without software designed for the purpose. Michael Hardy (talk) 18:52, 25 February 2016 (UTC)

Gimel function

Could someone please take a look at this article. The "Gimel" hebrew letter in the images looks like a Nun rather than a Gimel. A Gimel has a foot in the lower right.Naraht (talk) 22:00, 26 February 2016 (UTC)

Hmm, the article uses inline LaTeX, which we tend to discourage, but in any case it's producing $\gimel$ from the code <math>\gimel</math>, so if it's wrong, then it's actually wrong in our TeX rendering engine, not just the article. --Trovatore (talk) 00:38, 27 February 2016 (UTC)

The unicode for HEBREW LETTER GIMEL is ג, which looks more like what you describe, but less like what I've seen used to notate the gimel function. Maybe this is an issue of calligraphic style or something? Anyway, the version in the article looks like what I've seen in Jech, for example. --Trovatore (talk) 00:49, 27 February 2016 (UTC)

It looks like this is pretty much the way the character works in the font used by LaTeX, using the amssymb package. I did it on my local machine with \Huge and a fontsize of 20, and took a screenshot

. You can see that ther is a "foot", but it's very small, and when it's cut down to the size in the article, it's not surprising you can't see it. --Trovatore (talk) 21:34, 27 February 2016 (UTC)

In Jech's writings (http://matwbn.icm.edu.pl/ksiazki/fm/fm81/fm8116.pdf), you can clearly see the foot. What are the choices other than inline latex?Naraht (talk) 03:07, 28 February 2016 (UTC)

Why would you want to write mathematical notation to look different from the way professional mathematicians would write it? —David Eppstein (talk) 03:42, 28 February 2016 (UTC)

Exactly, the entry in Jeck's writing clearly shows the foot, the Wiki engine output of the LaTeX looks like a completely different Hebrew letter. The best comparison that I could give outside Hebrew would be if the LaTeX Capital Omega was shown without the two tails and as such it looked like an Omicron or a Latin Alphabet O. What can be we do make it look like what is in Jeck's article?Naraht (talk) 05:17, 28 February 2016 (UTC)

The letter should look like File:GimelLaTeX.png which clearly has the foot, the question is why the use of that letter in the article doesn't have the foot. Are the bottom lines of pixels being cut off? (Note, in this font, the letters are as different looking as ג and נ — Preceding unsigned comment added by Naraht (talk • contribs)

It probably depends on (1) your browser, OS, and what fonts you have loaded, and (2) the setting in your Wikipedia preferences for how you want math to be rendered. For me (using Chrome on OS X with the "MathML/SVG fallback" option turned on, which with that browser uses the SVG fallback rendering) the png file and the formula look basically the same. But this confusion of rendering combinations also means that trying to do something complicated to make it look better for you may be a waste of time if it ends up making things look worse for people with other settings and browsers. —David Eppstein (talk) 05:54, 28 February 2016 (UTC)

It turns out that there's a unicode GIMEL SYMBOL which is distinct from HEBREW LETTER GIMEL and looks like the one we want. We should probably change to use that, so that we don't have the sizing problems of inline PNG files. --Trovatore (talk) 06:06, 28 February 2016 (UTC)

Here's how it looks in inline text: ℷ. And inside {{math}}: ℷ. Presumably one advantage of using this unicode would be that it works in left-to-right text unlike the usual right-to-left ordering that you get when you use Hebrew text unicodes. The page I got the character from [3] says: "You need a font that supports this character to even have a hope of seeing it correctly in the browser." I'm not convinced that I have a good enough font because for me it just looks like some kind of sans-serif lambda instead of like the big image above. —David Eppstein (talk) 06:31, 28 February 2016 (UTC)

That's a pity. For me it looks almost exactly like the picture, but with sharper edges. Post a screenshot? --Trovatore (talk) 06:37, 28 February 2016 (UTC)

Ok, see [4] —David Eppstein (talk) 06:44, 28 February 2016 (UTC)

Hmm, yeah, on yours it looks the same as HEBREW LETTER GIMEL as far as I can tell. Well, not an ideal solution then. Still might be better than the PNGs? --Trovatore (talk) 06:47, 28 February 2016 (UTC)

My mobile modern browser is not able to display either Unicode character, for what it's worth. --JBL (talk) 15:53, 28 February 2016 (UTC)

Oh well. Nothing to be done, I guess. Someone should set a reminder to look at this again in a few years, see if browsers have caught up. --Trovatore (talk) 21:40, 28 February 2016 (UTC)

Modified KdV–Burgers equation and the List of dynamical systems and differential equations topics

Our list of new articles at User:Mathbot/Changes_to_mathlists includes a new article titled Modified KdV–Burgers equation. It was a total orphan, so I created one link to it in the "See also" section of the article titled Korteweg–de Vries equation. Then I decided to add it to the List of dynamical systems and differential equations topics, and I found that even "Korteweg–de Vries equation" is not listed there, and it's not immediately clear where within that list it would belong. Should the list itself get reorganized? Michael Hardy (talk) 00:51, 29 February 2016 (UTC)

Mar 2016

Discussion about generally considering articles from predatory publishers unreliable

There is a discussion here if that topic is of interest. It has been going on since Feb 26, but just wanted to make sure folks here are aware of it. Jytdog (talk) 18:13, 4 March 2016 (UTC)

A mathematics AfD, Wikipedia:Articles for deletion/Kolmogorov–Zurbenko filter, also appears to be connected to the same topic. —David Eppstein (talk) 18:19, 4 March 2016 (UTC)

List of things named after Friedrich Bessel

We now have a List of things named after Friedrich Bessel. Perhaps strangely, I found a list that was not empty but that had no internal links. I created those links. But possibly the article should be expanded. Michael Hardy (talk) 01:51, 6 March 2016 (UTC)

Polymath project

I don't know where to go, so I'm posting this here. There has been another polymath project solved! Can someone add this information to the "Problem solved" section of the article please? I think it can go under the heading of "Polymath proposal problem" under "Problem solved" section. This problem was going to become a polymath project, but someone else proved it so quickly before it becoming a polymath project (with number). However, I think it is another achievement worth mentioning in the article. Due to my limited mathematics background, I don't think I'm able to write about it as well as someone else with a major in mathematics or advanced knowledge in mathematics. If not, does someone know anyone, who has a strong background in mathematics, that currently still active on Wikipedia? So that I can ask him/her out personally. Thank you! Pendragon5 (talk) 00:23, 7 March 2016 (UTC)

Introduction to "Fractional Fourier entropy"

The article titled Fractional Fourier entropy begins like this:

Fractional Fourier entropy (FRFE) is based on two steps: (1) fractional Fourier transform (FRFT) that can transform images from the spatial domain to the “unified time-frequency domain”; and (2) Shannon entropy to extract features from the FRFT spectrums.

This doesn't set up the context properly. Could someone who knows this topic improve the intro? Michael Hardy (talk) 03:01, 6 March 2016 (UTC)

The article is now at AfD. Sławomir
Biały 13:33, 7 March 2016 (UTC)

AfC assistance

Greetings. If someone has a moment, there's an article over at AfC which needs some expert advice on whether or not it's notable. Assistance would be greatly appreciated: Draft:GBT - Generalised Beam Theory. Onel5969 ^{TT me} 18:31, 12 March 2016 (UTC)

Faddeev picture

In the Russian Wikipedia there is a picture of Dmitry Konstantinovich Faddeev. Could someone speaking the language have that picture uploaded to Wikimedia commons (or tell me how to link the Russian version)? YohanN7 (talk) 13:58, 10 March 2016 (UTC)

It is written there, in Russian, that this image is not free, thus fair use is required; and that this is fair use, since he is dead, therefore it is impossible to make another photo, and there is no free photo available. I have no idea, whether this is OK for Wikimedia commons, or not. Boris Tsirelson (talk) 16:11, 10 March 2016 (UTC)

As I understand it, fair use images (which this would be allowed as, since the subject is dead) must be uploaded directly to en.wikipedia rather than commons. —David Eppstein (talk) 18:14, 10 March 2016 (UTC)

Anyway, the source is here. Boris Tsirelson (talk) 19:02, 10 March 2016 (UTC)

Thanks. If it is non-free, the chances of using it "legally" is about zero in this Wikipedia. I have made similar attempts, and have been caught every time. (I like the Russian attitude towards bureaucratic problems; it is fair use because he is dead period. The English Wikipedia isn't that pragmatic. (I can understand the fear of an American-style lawsuit for $100 000 000.)) YohanN7 (talk) 11:10, 14 March 2016 (UTC)

The English Wikipedia allows fair use images for dead people. They have to be uploaded to the English Wikipedia (not commons) and have a fair use statement stating that it's fair use because the subject's dead, but I don't think there are more restrictions than that. As for lawsuits, I think the possibility is remote; the likely worst case is that we get a request to take the image down again. —David Eppstein (talk) 17:47, 14 March 2016 (UTC)

If that is the policy, I'll give it a try. Does it make a difference in which article it is used? For instance, the Élie Cartan picture is a no-no to use elsewhere according to Wiki-lawyers. YohanN7 (talk) 17:56, 14 March 2016 (UTC)

Yes, the picture should be used "only if its presence would significantly increase readers' understanding of the article topic, and its omission would be detrimental to that understanding" (WP:NFC). In practice that means it's definitely ok for a biography of the subject but more dubious as decoration on articles about the subject's mathematical results. —David Eppstein (talk) 18:20, 14 March 2016 (UTC)

Successive approximation, iteration(s) etc

For now, "Successive approximation" redirects to Successive approximation ADC(!), and "Iteration" disambigs to Iterated function, and Iterative method is a piece of applied mathematics. But it seems to me that both "Successive approximation" and "Iterations" are also mathematical terms. Or not? Boris Tsirelson (talk) 18:47, 13 March 2016 (UTC)

I agree, these are math terms, too. Various types of successive approximation methods are mentioned in Fixed-point iteration. It might be the best target for a math context redirect; Picard iteration already redirects there. My opinion is that Successive approximation itself should be a DAB page, because the psychology and electrical engineering uses of the term seem common, too. For iteration, there is just the Iteration article, which does briefly mention the mathematical uses. Iteration is the dominant link in the Iteration (disambiguation), so I think the math case is somewhat covered there, too. All the math type of iterative methods I know are from numerical analysis. Are there others? --Mark viking (talk) 20:03, 13 March 2016 (UTC)

"Are there others?" — I'd say, "Banach fixed-point theorem" (a.k.a. "Contractive mapping theorem" - redirect) is. And, yes, I like "Iteration#Mathematics", thank you for this point. Boris Tsirelson (talk) 20:36, 13 March 2016 (UTC)

The posting by Tsirel above was wrong: Successive approximation did not redirect to anything at the time he wrote that. But Successive Approximation (with a capital "A") did. I created the former redirect a few minutes ago. Michael Hardy (talk) 03:16, 16 March 2016 (UTC)

I have made Successive approximation into a disambiguation page. It needs further work. Michael Hardy (talk) 03:45, 16 March 2016 (UTC)

Very nice. Boris Tsirelson (talk) 06:43, 16 March 2016 (UTC)

Thank you. Michael Hardy (talk) 05:35, 17 March 2016 (UTC)

Rare case

Look, just for fun: Article needs a re-write (toned down from: WTF is this $hit).   :-)   Boris Tsirelson (talk) 18:50, 17 March 2016 (UTC)

Continued here. Boris Tsirelson (talk) 2:48 pm, Today (UTC−5)

not continued elsewhere, I'd like someone to (hopefully, sorry Tsirel) convert me to someone who likes Wikipedia. 90.199.52.141 (talk) 20:45, 17 March 2016 (UTC)

Exponential function

In this section of a talk page, two users say that the page titled Exponential function should deal only with the base-e (natural) exponential function and not other bases. Both of them seem to take the confused view that if other bases are allowed then the article is about the binary operation of exponentiation in general, as opposed to exponential functions of one variable. I agree with them that the binary operation of exponentiation should be, and is, the topic of a different article rather than this one. I wrote this brief explanation:

${\begin{aligned}(b,c)\mapsto b^{c}&&&{\text{This is exponentiation in general.}}\\[10pt]x\mapsto b^{x}&&&{\text{This is an exponential function}}\\&&&{\text{(the base is constant; the input variable is the exponent).}}\end{aligned}}$

Michael Hardy (talk) 01:31, 6 March 2016 (UTC)

Ask them if they even curry? 90.199.52.141 (talk) 20:40, 17 March 2016 (UTC)

I have set up an RfC on this at Talk:Exponential_function#RfC: Should exponential function be about exponentiation to any base?. The explanation above is not right, the question is whether the article should be about e^x like for instance Exponential function at Wolfram MathWorld, or whether it is about exponential growth and decay which is what exponential functions is general are mostly about and have the current contents moved to natural exponential function. Dmcq (talk) 23:40, 17 March 2016 (UTC)

Math in wikilinks broken?

See new thread at WP:VPT#Math in wikilinks broken? —David Eppstein (talk) 20:46, 17 March 2016 (UTC)

(That is, WP:VPT#Math inside wikilinks broken?.) —Tobias Bergemann (talk) 08:53, 18 March 2016 (UTC)

Stagnation of math pages

There is currently a discussion at User talk:Jimbo Wales#Search recent changes, and other Inspire Campaign proposals discussing the overly technical nature of some mathematical articles. The Beta_distribution has been singled out as an article with too much technical info, indeed there is much which could be cut from that article. The diff [5] on Euler's totient function has also been brought up as a case of WP:OWN. --Salix alba (talk): 06:55, 21 March 2016 (UTC)

Assault of the science blog churnalists

The Pi day brigade seems to have arrived late this year. Please keep a close watch on the article pi. There is a discussion underway at Talk:Pi, wherein a blog post is proposed to override a peer-reviewed secondary source written by the Borwein brothers. This could merit the attention of Wikipedia editors who are familiar with editing articles on mathematics and scientific topics, as opposed to Entertainment news topics which is what we seem to do mostly nowadays. Sławomir
Biały 19:44, 21 March 2016 (UTC)

For those interested in phylogenetics, and clade presentations

Could you have a look at this effort, here, to use clade diagrams to summarize pharma business acquisitions. My take at present is that the images created are devoid of standard quantitative meaning—nothing is captured by vertical and horizontal line lengths, as far as I can tell—and so they are a misapplication of this maths/graphic presentation method. Moreover, I argue that they are misleading (presenting a time axis, but not making spacing of events proportionate to the historical time differences), much harder to maintain (consider adding entries to a std Table versus this graphic), more likely to diminish article quality (in their ambiguity of content, again, over a std Table with clear headings), and therefore practically amenable to decay as a result. I would add to this, in this esteemed maths context, that they would make those who trained us, and other purists in methodology and meaning (and Edward Tufte more generally), turn in their graves/beds. After having a look at the User page and at a couple of pages linked on that sandbox page, leave your opinion here, regarding the overall effort? Thanks for your opinion. Cheers. Le Prof Leprof 7272 (talk) 01:37, 23 March 2016 (UTC)

Sorry about the inappropriate posting above. I have opened a discussion in the appropriate forum, here: Wikipedia_talk:WikiProject_Companies#Diagrams, for anyone who is interested Jytdog (talk) 03:28, 23 March 2016 (UTC)

Merge Semi-major axis and Semi-minor axis into the same article?

Another pair of doubly related articles are these. Should they be merged into the same article, maybe called Semi-minor and semi-minor axes? (Not set on title). M∧Ŝc²ħεИ_τlk 18:06, 22 March 2016 (UTC)

I think that is a good suggestion. --JBL (talk) 13:51, 23 March 2016 (UTC)

Consequences of a lack of consensus concerning inline text style mathematical formulae

CC: Template talk:Math#Consequences of a lack of consensus concerning inline text style mathematical formulae.

See Wikipedia talk:WikiProject Mathematics/Typography#Consequences of a lack of consensus concerning inline text style mathematical formulae. — Tentacles^{Talk or ✉ mailto:Tentacles} 22:04, 24 March 2016 (UTC)

Mathbot

Mathbot appears not to have put up any new changes in User:Mathbot/Changes to mathlists since March 23, but instead in User:Mathbot/Recent changes. GeoffreyT2000 (talk) 03:03, 27 March 2016 (UTC)

User:Mathbot/Changes to mathlists was just updated. But the other one might nevertheless be helpful to watch, as it lists articles with updated cleanup tags, not just new articles. —David Eppstein (talk) 22:17, 27 March 2016 (UTC)

User:AlexNewArtBot/MathSearchResult shows a few new articles that the others are not showing. An example is the new article Martin Scharlemann. 189.63.176.164 (talk) 22:27, 27 March 2016 (UTC)

Abstract Geometry creations languishing in Draft namespace

• Draft:Moduli stack of elliptic curves (edit | talk | history | links | watch | logs)
• Draft:Suslin homology (edit | talk | history | links | watch | logs)
• Draft:Principal orbit type theorem (edit | talk | history | links | watch | logs)
• Draft:Hamiltonian group action (edit | talk | history | links | watch | logs)
• Draft:Direct limit topology (edit | talk | history | links | watch | logs)

I was working through stale unedited pages in the Draft namespace and discovered several very abstract geometry creations from levels of "it exists" up to stub level quality. Several of these pages (as I've listed some examples above) had not been edited (since I came through looking at them) since 2014 in the draft namespace. I am not making any accusations regarding any individual editor or type of creation except to note that these draft title land grabs are begining to be more closely looked at if there is no positive progress on them. Does WP:Maths have any suggestions/interest in improving these to the point that they are ready to be promoted to mainspace? Hasteur (talk) 15:57, 22 March 2016 (UTC)

Draft:Principal orbit type theorem (edit | talk | history | links | watch | logs) should obviously be deleted. I do not think that Draft:Suslin homology (edit | talk | history | links | watch | logs) should be redirected to Singular homology, since to me it seems strange to have a redirect from the draft space into the mainspace. Perhaps a merge would be more appropriate, with a sentence or two mentioning Suslin's application of ideas of singular homology to algebraic varieties? Hamiltonian group actions are already discussed in moment map, which seems appropriate to me, so I don't see much value in a draft. Likewise Draft:Direct limit topology (edit | talk | history | links | watch | logs) seems like it would be a fork of final topology if it had any useful content, which it does not. In principle, an article on the moduli stack of elliptic curves would be worthwhile, but there is no useful content at the draft. Sławomir
Biały 16:37, 22 March 2016 (UTC)

@Slawekb: I redirected the homology article based off the only reference provided in the "proposed" draft [6] which said that Suslin was also known as singular. In practice, for these old unedited drafts is to redirect to a mainspace article that either is the subject or a section redirect to one that is appropriate. It's very flexible. I was primarily interested in having a Mathematics project member take a significant look at these examples created by one editor to help determine if some corrective action needed to be taken. Hasteur (talk) 17:31, 22 March 2016 (UTC)

First of all, I want to remind that they are drafts; that's why they exist in the draft namespace not in the main name space. The question should be whether the topics are notable or not not the actual states of content. I agree there is no value having drafts on nobodies (since they will never become main-name space articles). The above drafts, on the other hand, have potential to become main-namespace articles. Now I explain why they were created:

• Draft:Moduli stack of elliptic curves; this topic is currently not adequately covered in Wikipedia. There are sufficiently many technical points that it makes sense to have a separate article.
• Draft:Suslin homology is now in the main namespace.
• Draft:Principal orbit type theorem; this is an important result. Why delele? Am I missing anything? Wikipedia gone crazy?
• Draft:Hamiltonian group action; as pointed out, there is some overlap but it makes sense to discuss stuff like symplectic cut and linearization in a separate article.
• Draft:Direct limit topology; no really sure about this one. As far as I know, I couldn't find the materials in the page elsewhere in Wikipedia when the page was created. The merger is a good option but really there is no need for deletion.

More broadly, the issue seems to be the unclear nature of the draft namespace. I'm on the camp that there should be no deadline; some disagree, obviously. -- Taku (talk) 00:23, 23 March 2016 (UTC)

Some of the drafts you are defending have no useful content (e.g., moduli stack of elliptic curves actually has no content at all, principal orbit type theorem has no content, direct limit topology is just an irrelevant property about Cartesian products). Although there is no deadline, it doesn't seem like these drafts are under active development, and nothing much seems likely to emerge from the content that is there. If you actually want to do the work and learn about the moduli stack of elliptic curves, go ahead and read Lurie's notes and write an article. No one is stopping you. Sławomir
Biały 11:23, 23 March 2016 (UTC)

I agree. The only one of these articles that has anything useful is the one on Suslin homology; all the others have no content. Ozob (talk) 12:40, 23 March 2016 (UTC)

I don't think a direct limit topology is exactly the same thing as a Carterisan product topology; in algebraic topology, one typically works with the compactly generated weakly Hausdorff spaces and it would be useful to clarify the relationship between a direct limit in the category of those spaces and a direct limit in the point-set topology context (that's why I started a separate article.) In any case, as it appears to me, the issue is whether there should be a deadline or not; so I started Wikipedia_talk:Drafts#RfC: is there a deadline for a draft. -- Taku (talk) 00:36, 24 March 2016 (UTC)

"I don't think a direct limit topology is exactly the same thing as a Carterisan product topology": The draft under discussion concerns some property of Cartesian products, which is sourced to Milnor and Stasheff, not some other thing that you might be thinking of. But, like I said, there's no useful content at the draft, so whether you meant one thing or another isn't really that relevant. Sławomir
Biały 00:52, 24 March 2016 (UTC)

And there is no reason not to include materials not about a Cartesian product topology (e.g., stuff about CW complexes.) -- Taku (talk) 00:59, 24 March 2016 (UTC)

No, but why do you need a separate article to discuss Cartesian products of direct limits? Why can't this be covered in the article final topology? Sławomir
Biały 01:03, 24 March 2016 (UTC)

Why do you not see the point of having an article on direct limit topology? You do agree that notion exists, right? and is distinct from Cartesian product topology. Anyway, I don't think there is any issue here except the concept of deadlines. -- Taku (talk) 01:07, 24 March 2016 (UTC)

Yes, we have an article on the direct limit topology already. Your draft is about Cartesian products. Are you proposing that we should have an article about Cartesian products of direct limits? Because that's what your draft is about. Sławomir
Biały 01:38, 24 March 2016 (UTC)

No, we don't have it; Direct limit topology is a red link to me at least. I don't understand why you're so hang up with Cartesian product. The draft will eventually cover more topics. Isn't that why it's a draft? No one is proposing to limit the scope to Cartesian product of direct limits except you. -- Taku (talk) 07:29, 24 March 2016 (UTC)

It's another name for the final topology, to which that link now redirects. Sławomir
Biały 10:54, 24 March 2016 (UTC)

Clearly we don't speak the same language; What I have in mind is the direct limit of topological spaces. I don't know whether a direct limit topology refers to a direct limit of topological spaces or final topology. (It might depend on the field.) I have edited the draft (of course it still needs a ref etc.) -- Taku (talk) 23:43, 24 March 2016 (UTC)

Here we go again with the "in my field, everything is defined differently"... Sławomir
Biały 23:56, 24 March 2016 (UTC)

Taku, I must confess that I don't understand your point, either. Perhaps it would help if you could point us to a reference for the idea you're thinking of. Ozob (talk) 12:54, 25 March 2016 (UTC)

Like I said, by "direct limit topology", I was thinking of a direct limit of topological spaces not final topology; whence, the draft is not a duplicate. I said I don't know whether a "direct limit topology" is synonymous with "final topology" across the board. I suspect some people might use direct limit topology to refer the topology of the direct limit of topological spaces; see e.g., [7]. The relationship between direct limits and topology can be quite tricky and so it makes sense to have an article on the subject; that's all I'm saying. -- Taku (talk) 00:25, 26 March 2016 (UTC)

Our direct limit article says "Direct limits in the category of topological spaces are given by placing the final topology on the underlying set-theoretic direct limit", and this is also discussed in similar terms in the final topology article. So your reasoning for why this should be distinct from the final topology article remains unclear. —David Eppstein (talk) 00:49, 26 March 2016 (UTC)

I'm not disagreeing with the definition; for example, product topology and quotient topology are examples of a final topology. The direct limit topology is an example of a final topology. A quotient topology is a final topology but not a synonym of it; in the same way, I make a terminology cal distinction between a direct limit topology and final topology. (I suspect I'm not alone in that usage but I leave that to the others.) -- Taku (talk) 00:56, 26 March 2016 (UTC)

Based on the paper you linked above, I suspect you are alone. The paper's point is that sometimes the direct limit topology is not the right one. This sort of problem – that the category of topological spaces is badly behaved – has been known for a long time. See, for instance [8] or [9]. The solution is not to redefine the term "direct limit topology", but to either take the direct limit in another category (like the category of compactly generated spaces) or to take the direct limit in the category of topological spaces, but then construct a better behaved topological space from the direct limit (like replacing the topology with the compactly generated topology it generates). Ozob (talk) 03:06, 26 March 2016 (UTC)

(you misunderstood me. A direct limit topology is still defined as a final topology on the direct limit; I'm not redefining it; see the post below -- Taku (talk) 04:39, 26 March 2016 (UTC).)

(I appreciate everyone's patience with me, I meant it.) Please let me ask this way. Given a set, you can always put the final topology with respect to some given family of maps to the set. In particular, you can put the final topology on the set-theoretic direct limit of a direct system and the resulting topology is called the "direct limit topology". This topology is cited as an example in the final topology article rather than a synonym. Does it make sense to have an article about this topology separate from the article final topology? In particular to discuss the issue like the above? just as we have an article on quotient topology (correction to my early post: a product topology is initial not final, that was stupid). I had assumed the answer is yes. If the other editors disagree, then of course I will respect that. -- Taku (talk) 04:11, 26 March 2016 (UTC)

Well, you would have to find sources attesting to the notability of the direct limit topology, independent of its being an example of a final topology. But if you can do that, then I have no objection. Ozob (talk) 16:16, 26 March 2016 (UTC)

Why "independent"? For some reason, you keep misunderstanding me completely (this is too frustrating). I just wanted to ask: can we have an article extending the example (not as independent)? If the answer is no, I'm ok with that. However, I am not advocating for some non-standard weird usage. In any case, let's stop; the last thing I want is to waste everyone's time; I have redirected Draft:Direct limit of topological spaces to final topology. -- Taku (talk) 02:49, 27 March 2016 (UTC)

Well, I believe that all I am asking for is that the article subject be notable. As always, notability is not inherited from the notability of related topics (see WP:NOTINHERITED), which is why the sources should attest to the notability of the direct limit topology independently of the notability of the final topology. I raise this issue because I'm not sure that such sources exist. But if you can find them, then I have no objection. Ozob (talk) 04:07, 27 March 2016 (UTC)

(Maybe I misjudging "independent".) Does the paper I linked establish the notability? By googling, you can find tons of papers discussing direct limit topology (so there is no notability question.) Direct limit topology as a special case of a final topology is clearly notable. Going the other direction, a pushout is an example of a direct limit topology, that should also establish the notability. Also, the direct limit topology can be thought of a on-nose version of hocolimit; in other words, hocolimit is the homotopy-theoretic version of a direct limit topology. It's thus so natural to have an article on direct limit topology. -- Taku (talk) 04:51, 27 March 2016 (UTC)

A pushout is not an example of a direct limit because its index category is not cofiltered.

Homotopy colimits are not a good analogy. A colimit is a basic categorical construction; colimits appear everywhere we use equivalence relations, for example, so they are of interest not just in geometry and topology but also in combinatorics and analysis. A homotopy colimit requires additional data on the category to even define, and its usage is confined to homotopy theory (and areas which make contact with homotopy theory). And it's well-known that homotopy colimits can be completely different from colimits. For any topological space X, the homotopy colimit $*\cup _{X}*$ is the suspension of X, while the same colimit is trivially the one-point space. Ozob (talk) 21:06, 27 March 2016 (UTC)

About pushout, I know that: I was abusing the terminology a bit (since we're debating the question on notability not math): a pushout is an example of a colimit (and a direct limit is a colimit of a direct system). How about an article about colimit in topology? Is it your position that a "colimit in topology" is notable while "direct limit in topology" isn't? I don't think the analog is wrong if not perfect. One colimit is homotopy-theoretic and the other isn't; so obviously two notions are distinct (when did I claim colim = hocolim?) Yes, direct limit and colimit are category-theoretic concepts but they do get used in topology and I just don't get why we can't have an article about this topic in Wikipedia. The paper I linked and the issues you have listed show there are some issues specific to direct limits or colimits of topological spaces; that is, it is not taken care entirely by category-theory. It thus makes sense to have an article about the topic (or so I reasoned). -- Taku (talk) 03:07, 28 March 2016 (UTC)

I have no objection to an article about "colimits in topology" if you find reliable sources that affirm its notability. Nor do I object to "direct limits in topology", under the same proviso that you find reliable sources that affirm its notability.

Right now, I'm objecting to your analogy. Homotopy colimits are not the same as colimits in the category of topological spaces, nor are they the same as colimits in the homotopy category of topological spaces. Indeed, colimits in the homotopy category need not even exist (one of the standard examples is written up at [10]). Ozob (talk) 02:08, 29 March 2016 (UTC)

That's exactly why I put the qualifier "if not perfect". Ok, maybe "homotopy-theoretic" was a poor word choice; maybe homotopically has been better, since I wasn't referring to the homotopy category. (Note since a homotopy category is a different category, you can't even compare hocolim and colim if the former is meant colim in the homotopy category). I believe I'm correct to understand that in some context in algebraic topology hocolimit of spaces gives a correct answer as opposed to the colimit of spaces (why or how are irrelevant to us.) The point I'm making is that I find it strange that we're allowed to discuss hocolim of space but not colim of spaces. I don't think the final topology is the best place since the article is really about equipping a set with a topology in a certain way not exactly about the construction. Also I have already given one ref and Googling will many more. Of course other editors may disagree with my understanding of the notability and I'm not pressing the issue. -- Taku (talk) 03:10, 29 March 2016 (UTC)

Guidelines about living scientists

See Wikipedia_talk:WikiProject_Biography/Science_and_academia#guidelines_about_living_scientists--Alexmar983 (talk) 06:21, 30 March 2016 (UTC)

Probability distributions -- variates

Maybe I'm reading into this incorrectly, but how can Elliptical distributions be in the Location-scale family, when location-scale families are univariate and elliptical distributions are multivariate? I'm working through classifying the variety of probability distributions on Wikidata using d:Property:P279, so this is how I came about this question. (Basically, am I doing something wrong? :D) --Izno (talk) 19:37, 30 March 2016 (UTC)

Indeed, usually location-scale families are assumed to be univariate. But sometimes they are not. For instance, see Def. 2.3 in lecture 17 here: [11]. Boris Tsirelson (talk) 20:20, 30 March 2016 (UTC)

Ah, okay. Will make the necessary amendments. Thanks! --Izno (talk) 20:28, 30 March 2016 (UTC)

Apr 2016

Maryna Viazovska

I've created a stubby new article titled Maryna Viazovska. It could probably use more work. Michael Hardy (talk) 16:13, 31 March 2016 (UTC)

And now it's been proposed for deletion — see Wikipedia:Articles for deletion/Maryna Viazovska. —David Eppstein (talk) 19:40, 31 March 2016 (UTC)

Would everybody who can opine on this post their thoughts at this page for discussing the proposed deletion. Michael Hardy (talk) 03:29, 1 April 2016 (UTC)

Update: So far the Keep sentiment seems to be ahead of the Delete sentiment. Michael Hardy (talk) 20:31, 3 April 2016 (UTC)

April 2016 Disambiguation links

The following math-related terms are in our list of the 1,000 most linked disambiguation pages for April 2016. Any help in fixing links to these pages would be appreciated:

• Decomposition method (6 links)
• Function field (5 links)
• Grothendieck duality (5 links)
• Leibniz's rule (5 links)
• Sieve method (5 links)
• Tree diagram (5 links)

Cheers! bd2412 T 04:10, 5 April 2016 (UTC)

RFC on Gödel's incompleteness theorems

See Talk:Gödel's incompleteness theorems#RfC formal system for a formal RFC on whether Gödel's incompleteness theorems should espouse the viewpoint "that formal systems are entirely formal and consist of only formal content" (see RFC for full proposal), and please weigh in if you have an opinion. —David Eppstein (talk) 18:50, 5 April 2016 (UTC)

The "nowrap" template doesn't work.

In the article titled Magma (algebra) one finds this code:

{{nowrap|''M'' × ''M'' → ''M''}}

But what I see is this:

M

× M → M

The whole point of the "nowrap" template is to prevent this kind of wrapping. Michael Hardy (talk) 19:11, 2 April 2016 (UTC)

I presume you mean the one in the lead. It works for me, however wide I make the window it is never broken by wrapping. Even if I make the window as narrow as possible and the text as large as possible, which actually makes the M × M → M too wide for the window on its own, it still is one one line. Testing it in this paragraph it also works as expected, and the CSS looks fine.--JohnBlackburne^words_deeds 19:54, 2 April 2016 (UTC)

WP:VPT might be a better place for finding out why this might be happening and how to fix it, since it is more general than for just mathematical formulas. But I have also been seeing the same thing with the {{math}} template, which is also supposed to not wrap but perhaps implements that differently. —David Eppstein (talk) 19:55, 2 April 2016 (UTC)

Same method; white-space: nowrap; by way of the .nowrap class. -- [[User:Edokter]] {{talk}} 21:21, 2 April 2016 (UTC)

I can reproduce it with up-to-date Chrome 49.0.2623.110 (64-bit). The line break seems to happen after the arrow for me, if I change the window to a suitable width to force the break to appear. — Carl (CBM · talk) 21:07, 2 April 2016 (UTC)

It appears to be a Chrome bug that allows breaks when nested element are encoutered, in this case, <i>...</i>. -- [[User:Edokter]] {{talk}} 21:21, 2 April 2016 (UTC)

Yes. I see it in Chrome, but not in IE. YohanN7 (talk) 13:49, 7 April 2016 (UTC)

A new draft at AFC for your consideration

Please review Draft:Kundu equation. If you do not know how to perform an AFC review please simply post your assessment to the draft's talk page. Roger (Dodger67) (talk) 11:50, 24 March 2016 (UTC)

I'm a mathematician, but confused also. I think, but am not sure, that it's the same as the Eckhaus equation, also known as the Kundu–Eckhaus equation.

Another issue is that the creator of Draft:Kundu equation has the username Anjan Kundu, which implies conflict of interest. Joseph2302 (talk) 18:54, 7 April 2016 (UTC)

The Kundu equation, also called the Kundu-NLS equation is a generalization of a nonlinear Schrodinger equation. The Kundu–Eckhaus equation is a specialization of the Kundu-NLS equation. See for example, [12]. --Mark viking (talk) 19:14, 7 April 2016 (UTC)

"Surface"

The usage and topic of surface is under discussion, see Talk:Surface -- 70.51.45.100 (talk) 05:50, 8 April 2016 (UTC)

\int\limits

יהודה שמחה ולדמן (talk · contribs · deleted contribs · logs · filter log · block user · block log) is apparently going around and changing every integral on Wikipedia from this:

$\int _{a}^{b}f(x)\,dx$

to this:

$\int \limits _{a}^{b}f(x)\ dx$

Note: In addition to having the limits placed far above the integration sign, the thin space between the integrand and differential is replaced by a full space. Do we agree on the global application of this style decision to all of our math articles? Sławomir
Biały 18:57, 31 March 2016 (UTC)

I oppose this LaTeX construction in all cases -- I do not think there is ever a good reason for it. --JBL (talk) 19:01, 31 March 2016 (UTC)

From some LaTeX documentation I remember that this form is recommended only for multiple integrals (\iint, \iiint, \idotsint). Boris Tsirelson (talk) 19:11, 31 March 2016 (UTC)

I am happy to restrict my comments to the case of single integrals. --JBL (talk) 22:54, 31 March 2016 (UTC)

Limits above and below are fairly rare in my experience. Placing a limit below for integration over a region is the only common use case I know. The changing of typographic styles for the sake of personal preference in an already existing article is discouraged, in the same way that we discourage LaTeX <-> HTML conversions. --Mark viking (talk) 19:20, 31 March 2016 (UTC)

I'm glad someone brought this up. I didn't want to step on anyone's parade, but I see no good (or even bad) reason for making these changes. Bill Cherowitzo (talk) 22:26, 31 March 2016 (UTC)

So should \int\limits_a^b generally be changed to \int_a^b? I.e. is $\int \limits _{a}^{b}$ always changed to $\int _{a}^{b}$? —  crh ₂₃  (Talk) 16:58, 6 April 2016 (UTC)

While there seems to be agreement that \int_a^b is more common than \int\limits_a^b and would be preferable in most instances, my opinion is that going from article to article changing typographical style according to personal preference was the main problem here. If the editor in question used \int\limits_a^b in a completely new article, it would be a little odd, but not a big problem. So my sense is that going from article to article enforcing \int_a^b is problematic, too--it could lead to pointless edit wars. I'd be in favor of adding the preference for \int_a^b to MOS:MATH instead. --Mark viking (talk) 18:04, 6 April 2016 (UTC)

If this is indeed consensus (which looks to be likely), an addition to MOS:MATH would be great. My reason for asking is this could be added to the AWP list of typos, to be automatically corrected whenever WP:AWB is used to edit a page. Any thoughts? Would there be a problem having \limits blindly removed whenever it occurs immediately after \int?—  crh ₂₃  (Talk) 20:37, 6 April 2016 (UTC)

Possibly, because constructions like $\iint \limits _{D}$ are completely normal. I can't think of a one-variable situation where one would want to use \limits, though, so maybe changing that situation is fine. Ozob (talk) 12:30, 8 April 2016 (UTC)

The only possible problem I can see is if someone uses \int\!\!\!\int\limits_D to produce that. Could that happen? —  crh ₂₃  (Talk) 14:05, 8 April 2016 (UTC)

Who knows? We have a lot of editors, registered and anonymous, with all levels of TeX. I guess it does happen somewhere. Can AWB do the replacement only if there is no "!" before "\int\limits"? Boris Tsirelson (talk) 15:42, 8 April 2016 (UTC)

Yes, it is a pretty full regex engine. The problem is predicting any other weird ways of using \int for multiple integrals. —  crh ₂₃  (Talk) 16:10, 8 April 2016 (UTC)

I can think of a one-variable situation which \limits would be used. Normally in an inline, as opposed to displayed, setting, things like \lim_{x\to a} and \sum{n=1}^x have subscripts and superscripts to the right rather than directly above and below, whereas in a a displayed setting they are above and below. But in some instances (not most) it makes sense to use the format used in displayed setting when one is in an inline setting. This can happen when there are no lines of text directly above and below the line in which the notation appears. Michael Hardy (talk) 21:34, 10 April 2016 (UTC)

Fortifying wikiquanta

This project is mostly physical (and advertised on wikiproject physics), but may interest some mathematicians, too. Boris Tsirelson (talk) 11:02, 14 April 2016 (UTC)

More help needed at AfC

Greetings and salutations. Draft:Dragonfly algorithm is a draft sitting at AfC which I could really use input on. Thanks in advance.

Oh, and if you're in the mood, there is a stale draft, Draft:Subdivision curve, which I also could use some help evaluating. Thanks in advance. Onel5969 ^{TT me} 13:25, 17 April 2016 (UTC)

New Math rendering now on Beta

https://twitter.com/physikerwelt/status/720310670512631808 --Physikerwelt (talk) 18:08, 14 April 2016 (UTC)

My first thought was: what's new? MathML already worked on Firefox. Then I noticed I now get SVGs in Chrome. Unfortunaltely, they are just as ugly as the PNGs, but at least they're scalable :) Can we at least switch to STIX for the default font? Computer "Modern" looks incredibly midevil... -- [[User:Edokter]] {{talk}} 19:21, 14 April 2016 (UTC)

@Edokter: technically that's not a problem, but is ther consensus for that change?--Physikerwelt (talk) 21:05, 17 April 2016 (UTC)

Physikerwelt, I'm positive an RfC with both fonts being showcased (with screenshots) will establish a consensus soon enough. -- [[User:Edokter]] {{talk}} 10:45, 18 April 2016 (UTC)

The beta page can be found at http://en.wikipedia.beta.wmflabs.org/wiki/Math --Salix alba (talk): 23:13, 14 April 2016 (UTC)

I think it looks beautiful. Ozob (talk) 02:24, 15 April 2016 (UTC)

Darboux frame

I think in the "Definition" section that "(the unit tangent)" and "(the unit normal)" should be interchanged. That is "(the unit tangent)" should be where "(the unit normal)" is, and "(the unit normal)" should be where "(the unit tangent)" is. MGilly9 (talk) 09:26, 18 April 2016 (UTC)

If you mean that the formulas for "unit tangent" and "unit normal" should be interchanged in Darboux frame § Definition, you are wrong. If you mean that the ordering of the three unit vectors must be changed, this is not so clear. The order of the vectors in a frame is a question of convention, and any convention is valid. However, it is not natural that the two tangent vectors are separated by the normal vector, and avoiding this imply to exchange the first two vectors, as you are asking for. Nevertheless we have to follow the literature, and before making this exchange, one has to look on the reliable references for the most common convention. D.Lazard (talk) 10:13, 18 April 2016 (UTC)

It looks like there are some equations with T, t, u whose left-hand sides should be double-checked. Sławomir
Biały 11:53, 18 April 2016 (UTC)

For those with any knowledge of clade-type computations/presentations

Could you have a look at this effort, here, to use clade diagrams to summarize pharma business acquisitions. My take at present is that the images created are devoid of standard quantitative meaning—nothing is captured by vertical and horizontal line lengths, as far as I can tell—and so they are a misapplication of this maths/graphic presentation method. Moreover, I argue that they are misleading (presenting a time axis, but not making spacing of events proportionate to the historical time differences), much harder to maintain (consider adding entries to a std Table versus this graphic), more likely to diminish article quality (in their ambiguity of content, again, over a std Table with clear headings), and therefore practically amenable to decay as a result. I would add to this, in this esteemed maths context, that they would make those who trained us, and other purists in methodology and meaning (and Edward Tufte more generally), turn in their graves/beds. After having a look at the User page and at a couple of pages linked on that sandbox page, leave your opinion here, regarding the overall effort? Thanks for your opinion. Cheers. Le Prof Leprof 7272 (talk) 01:37, 23 March 2016 (UTC)

Sorry about the inappropriate posting above. I have opened a discussion in the appropriate forum, here: Wikipedia_talk:WikiProject_Companies#Diagrams, for anyone who is interested Jytdog (talk) 03:28, 23 March 2016 (UTC)

Jytdog moved the question to a new forum, the one where it is least likely to be viewed with rigour, see last comment and link. I reply there. I stand by the fact that maths is an appropriate venue to call for experts, and that it was appropriate to call out to you you at this location, to ask your input. All coming from mathematics, I would appreciate if you state for the record, if you have any real knowledge on this matter (have ever actually done a cladogram-type computations). Transparency, please. Le Prof Leprof 7272 (talk) 15:45, 23 April 2016 (UTC)

Need insights

See Talk:Area of a circle#Circular Argument. I am not asking for support for either side, but for input from those with higher math education than either me or the IP.--Jasper Deng (talk) 20:14, 23 April 2016 (UTC)

Changes by Yonathanyeremy

I just reverted a change by Yonathanyeremy (talk · contribs) and looking at their other ones I can't see anything else that I agree with. Anyone else like to have a quick check and perhaps say what on earth is happening thanks. Dmcq (talk) 13:07, 25 April 2016 (UTC)

I saw this edit to Paul Erdős and didn't care enough to try to decide whether to revert. Many of the others are similar, changes to links that are pretty innocuous and neither obviously improvements nor obviously vandalism. (Sorry this is probably not helpful.) --JBL (talk) 22:17, 25 April 2016 (UTC)

I've undone a few more of his changes. I'm curious to know why he's doing these. Ozob (talk) 23:57, 25 April 2016 (UTC)

Cyclic function

We have a short article titled cyclic function that is not in very good shape right now. In particular, can anyone understand this final sentence?:

Cyclic functions can be used in solving problems by substituting a function for its cyclic pair.

Michael Hardy (talk) 21:31, 25 April 2016 (UTC)

Tentatively, it's about the universe of mathematical problem solving: there is a class of problems in which one is to solve an algebraic equation involving a cyclic function (or one with a similar property), and by iterative substitution one arrives at an equation that is more easily human-solvable. --JBL (talk) 22:14, 25 April 2016 (UTC)

Based on Google, it looks like "cyclic function" usually means "periodic function". So even though there's at least one prominent hit for the meaning of "cyclic function" given in the article, I think it might be better for cyclic function to redirect to periodic function. Ozob (talk) 00:04, 26 April 2016 (UTC)

Kundu equation (again)

• Anjan.Kundu (talk · contribs · deleted contribs · logs · filter log · block user · block log)
• Kundu equation (edit | talk | history | protect | delete | links | watch | logs | views)
• Eckhaus equation (edit | talk | history | protect | delete | links | watch | logs | views)

Anjan.Kundu is editing both of these articles, and adding content about the Kundu-Eckhaus equation to Kundu equation. In my view, the Kundu-Eckhaus & Eckhaus equations are the same equation, and so all the information should be on that article. The Kundu equation is a separate equation IMO. Thoughts? Joseph2302 (talk) 12:07, 26 April 2016 (UTC)

Dear Editors,

Let me explain this issue briefly.

An integrable generalization of the nonlinear Schroedinger equation with additional quintic nonlinerity and a nonlinear dispersive term given by

$\psi _{t}+\psi _{xx}-2c|\psi |^{2}q+\kappa ^{2}|\psi |^{4}\psi \pm 2i\kappa (|\psi |^{2})_{x}\psi =0,$

proposed in (kundu|1984) is known as the Kundu-Eckhaus equation (more details on this equation with its other aspects, applications and references can be found in my Sandbox). Eckhaus equation introduced later is a particular case of the Kundu-Eckhaus equation (with $c=0$) and therefore not the same equation as incorrectly mentioned in that Wiki page. Note that while the Eckhaus equation is linearizable, the Kundu-Eckhaus equation is reducible only to the nonlinear Schroedinger equation through the same transformation. On the other hand, the Kundu-Eckhaus equation can be derived from the Kundu equation as a particular case. Therefore IMO there may be three logical options: (1) Eckhaus equation can go as a subsection under Kundu-Eckhaus equation, (2) Kundu-Eckhaus equation can go as a subsection under Kundu equation, (3) Kundu-Eckhaus equation can go as an independent entry.

Hope to get your valuable suggestion/opinion/advice. Anjan.kundu (talk) 06:45, 27 April 2016 (UTC) April 27, 2016

Hello Dr. Kundu. Thank you for adding this to Wikipedia. I think your contributions are valuable and interesting. A slight caution is that, generally, Wikipedia discourages editing a topic that one has too close a connection to (for example, articles about eponymous concepts named after ourselves). Some editors can be a little aggressive in their pursuit of stamping out apparent "self-promotion". Of course, when a concept is named after a person, that person is also often uniquely the most qualified person to write about that topic, so it's something of a mixed bag. I, for one, think your contributions are good, and not overly self-promotional, but please don't take it personally if others see the situation differently. My advise would be to edit other articles in your area of expertise, since you obviously know the literature in this field quite well. I've made some edits at Kundu equation (mostly spelling corrections), but it needs some more work, and I'm sure other editors will eventually want to clean it up some more. Thanks, Sławomir
Biały 14:29, 27 April 2016 (UTC)

Hello Prof. Slawomir Biaty, Thank you very much for your valuable comments and advice. Hope other editors would also agree to it with more suggestions and finally the 'tag' marked now to the contribution of Kundu equation could be removed.

With best regards. Anjan.kundu (talk) 05:09, 28 April 2016 (UTC)

Dashboard course

It appears that a Dashboard.wikiedu.org course (Calculus I at Howard University) is getting active with 5 student editors working on several calculus related pages. I have just reverted two of them on Integration by substitution before I realized that this was part of a sponsored program. I believe my reverts were the correct thing to do, but I am wondering whether or not I should have been more proactive in pointing out what the problems with the edits were. There are several issues involved here that I think should be addressed by project members. I have seen this type of project several times already and in each instance the program has left messes on several pages that have had to been cleaned up by us. Is there a way to inform the program directors that while the intentions of this program may be good and noble, the direct consequence is that a lot of unnecessary cleanup work is being created for us and perhaps there are other ways to achieve their ends without over-burdening the project editors. As WP editors we do not act as referees for the material presented on the pages, we do not evaluate, nor correct – unless backed up by a reliable source. By an extension of the philosophy upon which that position is based, should we be acting as teachers of the, in this case, Howard University students? Howard U. is not paying us a salary, nor does it have any control over who we are; I think the university should be concerned about that. Any comments, suggestions, etc. Thanks. Bill Cherowitzo (talk) 04:48, 26 April 2016 (UTC)

There's the education Noticeboard, which can be used if needed. Joseph2302 (talk) 06:42, 26 April 2016 (UTC)

Wikipedia:Education noticeboard is at WP:ENB: WP:EN redirects to Wikipedia:Naming conventions (use English) —  crh ₂₃  (Talk) 09:44, 26 April 2016 (UTC)

Link fixed, thanks. Joseph2302 (talk) 12:02, 26 April 2016 (UTC)

Or you could contact Ian (Wiki Ed) who appears to be the Wikipedia education person associated with Wikipedia:Wiki Ed/Howard University, Washington, DC/Calculus I (spring 2016). Joseph2302 (talk) 06:47, 26 April 2016 (UTC)

Also Joel Lewis reverted some edits to limit of a function that were related to this program. It looks like all edits to these articles were reverted and that the edits were made by at least three distinct students in that program. This suggests that the students are encouraged not only to review the articles, but also to edit them. That is a problem, in my opinion. While there is no rule against people unfamiliar with a topic making edits, typically for major edits such as these, one should generally expect that the editor is familiar both with how Wikipedia works, and with the topic area. Correction: this edit to antiderivative was reverted, by me. Sławomir
Biały 09:57, 26 April 2016 (UTC)

I've notified Ian (Wiki Ed) about this discussion, so hopefully he'll be able to help/advise. Joseph2302 (talk) 12:02, 26 April 2016 (UTC)

I have to say that I'm distressed by this whole situation. These students are being asked to contribute to well-developed articles written by experts, and they just don't have the competence to do so. Their contributions so far have shown they don't understand calculus and they don't know how to write. The students who haven't edited yet are unlikely to be any better. I'm sure they're being graded on their contributions; do they all get an F because they can't write with style and depth of professional mathematician? They're in an impossible position. Ozob (talk) 12:41, 26 April 2016 (UTC)

I just noticed that the students are required to edit the articles: "Add 1–2 sentences of new information, backed up with a citation to an appropriate source, to a Wikipedia article related to the class." This is most worrying indeed. It seems like the students are editing mostly the leads of articles, which is in fact the hardest part to write, requiring the most experience (both as a Wikipedian and as a content expert). I think these assignments should be put an end to. Sławomir
Biały 12:57, 26 April 2016 (UTC)

I looked through the case studies at [13] and was impressed. There are some excellent ideas for student editing of Wikipedia. However, a common thread seemed to be that the students can be reasonably expected to be knowledgeable about the articles they are supposed to edit. For example, the students might be asked to write a research paper on a topic not covered in Wikipedia; writing the research paper already makes the student more knowledgeable about the subject than what can be gleaned from Wikipedia, so it's not unreasonable to ask them to write an article. Another common thread is that the process is long, usually spanning a whole quarter or semester. Often the students must submit drafts for the instructor to review, so they are not permitted to do a slapdash job. I expect that a course structured like some of the case studies but focused on mathematics would be excellent both for the students and for Wikipedia. Ozob (talk) 23:29, 28 April 2016 (UTC)

Yes, I agree with this. But, to reiterate a point I think we agree on, that was emphatically not the case here. One does not simply unleash the students willy-nilly with no preparation. There is an expectation that, if they are going to edit the encyclopedia, that they actually should do a good job, not turn Wikipedia into a personal scratchpad for half-baked (or indeed, completely unbaked) homework assignments. Sławomir
Biały 00:05, 29 April 2016 (UTC)

Yes, some of those case studies look like valuable projects. I did note that science and mathematics topics are mostly missing and I expect that this is partially due to the fact that this type of writing is more challenging and harder to get right. These difficulties can be overcome, but I think it requires that the instructor be more directive and involved with the students than would normally be the case. However, this may cause a problem since topical specialists may not feel comfortable in this expanded role, and some would certainly feel that the more time spent on writing issues, the less time will be available to devote to the subject at hand. I think we have seen what results when an instructor doesn't move in this direction. Bill Cherowitzo (talk) 04:27, 29 April 2016 (UTC)

Under the conditions Ozob mentions, it can turn out pretty good, even for technical articles. The section S-matrix in one-dimensional quantum mechanics is the result of such a project. YohanN7 (talk) 08:26, 29 April 2016 (UTC)

There's no reason not to revert substandard edits. You should treat them like any other Wikipedia editor (good or bad); their additions need to be high enough quality, and they must be reliably sourced. And you're right - it isn't your job to clean up after them. Let me figure what's going on and try to steer them in a better direction. My apologies for the trouble caused. Ian (Wiki Ed) (talk) 13:39, 26 April 2016 (UTC)

May 2016

RfC article title: "Area of a circle" or "Area of a disk"

There is an RfC at Talk:Area of a disk#RfC article title: "Area of a circle" or "Area of a disk" that would benefit from the insight of members of WPM. Please direct your comments there. Sławomir
Biały 17:04, 3 May 2016 (UTC)

Selection principle

The article titled Selection principle could probably use some work in the intro section. Michael Hardy (talk) 21:28, 4 May 2016 (UTC)

Article Importance Ratings

I've been looking at the "area of a disk"/"area of a circle" article...noticed it's rated "low importance"...was wondering why...it would seem it should be the exact opposite (that is, important for Wikipedia to have a good article on such a fundamental/elementary/and widely taught topic)...it seems the articles rated highly important are often of a very advanced nature (which may be fine, but less advanced though very important articles like this are also highly important)..I went to the pages on the ranking but it appears there has been no activity over there for many years...so posted here...are these ratings irrelevant at this point and of no consequence to anything? or should they be changed/done away with because they interfere with editorial activity?68.48.241.158 (talk) 14:11, 4 May 2016 (UTC)

It is not really a rating (like "C class" is), more of an assessment of importance. You can change the assessed importance yourself by editing the talk page. YohanN7 (talk) 14:39, 4 May 2016 (UTC)

okay, I suppose it was implemented to draw editorial attention toward certain articles? Does it actually do this in some manner or is it basically irrelevant (as I said the policy pages on it haven't been touched in some five years)?68.48.241.158 (talk) 14:54, 4 May 2016 (UTC)

I think this topic is so widely studied that its importance should be at least "mid". —David Eppstein (talk) 15:59, 4 May 2016 (UTC)

I have never liked the term "importance" because its meaning to editors is ambiguous. Is it a rating of how important a topic is in the field or is it an indication of the need for editors to work on the page? I think the latter may have been the intended meaning but the former is probably the interpretation of the casual editor. I prefer the use of the term "priority" (which we are allowed to use) as this more clearly indicates a directive to editors. With this terminology I interpret (and I am sure that not everyone will agree with this) a high priority rating as meaning an article that is important in the first sense that is in need of a lot of work by editors and a low priority rating as one that means not much attention needs to be paid to the article (could mean that the article is in good shape or that it is not a significant contribution). Mid priority would be the grab bag of whatever is left over. This aspect of the rating system has been discussed in the past and I am pretty sure that no general agreement was ever reached. Bill Cherowitzo (talk) 19:37, 4 May 2016 (UTC)

okay, seems like a mechanism that doesn't have a clear philosophy/utility behind it...so probably inconsistently used...it could be harmful to the project if fundamental articles aren't being looked at by serious editors because they've been labeled of low importance...but my feeling is the label is entirely ignored and irrelevant at this point...68.48.241.158 (talk) 21:29, 4 May 2016 (UTC)

I don't think it's entirely ignored; at least, I have occasionally used the chart of articles by quality+importance at Wikipedia:WikiProject Mathematics/Wikipedia 1.0 to help me see what needs more work. —David Eppstein (talk) 22:17, 4 May 2016 (UTC)

Need some free media

I'm looking for a "free" version of the image on the last page of this PDF: [14]. I would like to use it in the new section at pi, with a caption about Queen Dido and the isoperimetric problem. Does anyone know how we might find such a thing? (I was going to add: short of flying to Rome, but the irony is I actually will be in Rome. Still, let's not...) Sławomir
Biały 22:55, 4 May 2016 (UTC)

I reverted this, thinking that I had found a better image (http://math.arizona.edu/~dido/LordKelvin1894.pdf) but I don't think that PDF is free either. (I was thinking that it's published before 1900, but that would mean that I could probably go and make my own scan of the original, but that using someone else's scan without permission would be non-free.) So, if there's a "free" pdf out there, of either image, I'd appreciate to know where. Sławomir Biały (talk) 23:19, 4 May 2016 (UTC)

File:Dido purchases Land for the Foundation of Carthage.jpg maybe? It's not Rembrandt but it is Dido and the oxhide. —David Eppstein (talk) 23:58, 4 May 2016 (UTC)

Actually, I meant the image on the second page, showing a very circular Carthage, drafted by Lord Kelvin. Sławomir Biały (talk) 00:27, 5 May 2016 (UTC)

It's online at a bigger resolution at https://archive.org/stream/proceedings14roya/#page/112/mode/2up which (in the detail page for the proceedings) lists its copyright status as "not in copyright". So I think you could grab a copy from there to use. —David Eppstein (talk) 00:36, 5 May 2016 (UTC)

I grabbed a copy from Google Books. I'm hoping that public domain content hosted by Google is still suitable for derivative free works like the image I placed in the article. Sławomir Biały (talk) 01:03, 5 May 2016 (UTC)

Is this image label incorrect ?

Please see: [[15]]

73.4.14.51 (talk) 14:28, 6 May 2016 (UTC)

It is correct; explained there. Boris Tsirelson (talk) 15:55, 6 May 2016 (UTC)

Message for: RfC: Change Default Math Appearance Setting to MathML (Follow Up) Suggestion

Hi, so I don't know where the best place to post this is. I have this RFC that is highly applicable to this WikiProject that should be advertised here. — Preceding unsigned comment added by Hungryce (talk • contribs) 02:15, 23 April 2016 (UTC)

Looking at T131177 it looks like "Enable MathML by default" is going ahead. Probably your last chance to comment. --Salix alba (talk): 18:26, 6 May 2016 (UTC)

Some people have objected to firefox using MathML which is patchy. It looks like Firefox will get SVG as the default.--Salix alba (talk): 18:32, 6 May 2016 (UTC)

Takahiro4, Kawarabayashi, etc.

Could I get some more eyes on our WP:BLP article on Japanese graph theorist Ken-ichi Kawarabayashi, please? Takahiro4 has been making a mess of it. It's not the only recent problem involving this editor; see User talk:David Eppstein#kawarabayashi article (or Takahiro4's contributions) for context. —David Eppstein (talk) 18:11, 4 May 2016 (UTC)

I don't read Japanese, so it's hard to verify the added material at Ken-ichi Kawarabayashi. (User:TakuyaMurata perhaps could check it.) I've corrected some of the obvious grammatical problems there, and removed a sentence about what conferences he likes to attend as not especially noteworthy. Sławomir
Biały 19:10, 4 May 2016 (UTC)

I've checked some assertions that were backed by the Japanese source. Some minor points (e.g., the name of the supervisor) didn't appear in the source so, for those claims, I changed the ref to CV. The secondary source is better than the primary one (CV), but since the claim is not extraordinary, the CV is probably good enough. -- Taku (talk) 23:42, 4 May 2016 (UTC)

Thanks, both of you. —David Eppstein (talk) 23:55, 4 May 2016 (UTC)

The editor seems to be really keen on picking a fight with others. It isn't clear to me why, but I suspect he is not long for the English Wikipedia if his behavior continues in this vein. I was tempted to bring the matter to ANI, as the editor is technically over 3RR at π (against no less than four distinct editors), and has resorted to petty name-calling. I still hold out hope though that this will blow over. I do find it rather unpleasant that the discussion of my recent addition to π took this rather ugly turn, and although I certainly welcome discussion, I wish that the circumstances surrounding that discussion had been more amicable. Personally, I think Takahiro4 should be blocked, but discussion should be allowed to continue if there are any other editors wishing to take up the mantle. Sławomir
Biały 11:23, 5 May 2016 (UTC)

Disruption continues at pi. At some point, I think ANI is called for. I am convinced that the editor is just trolling. On the talk page, he requested a section on Fourier series, and now is intent on adding templates against policy. I think it's time this editor be blocked. He is wasting the time of productive editors. Sławomir
Biały 15:13, 8 May 2016 (UTC)

Arithmetic of quadratic forms – amusing typo

Just as one writes [[cat]]s so that the reader sees "cats" and clicks on it and sees the article titled "cat", someone typed [[arithmetic of quadratic form]]s in an article. That doesn't make sense and I changed it to [[arithmetic of quadratic forms]]. However, we currently have no article titled Arithmetic of quadratic forms. Should we? And can someone here start the article? Michael Hardy (talk) 17:14, 8 May 2016 (UTC)

Can someone create a very simple graph in Maple?

It was pointed out to me that the graph File:Champernowne_constant_logscale.svg used in Champernowne constant has a mistake: the dots corresponding to the 41-st digit is out of place (it should be at height 10^{2504}. Not sure how that happened! :/ Anyway, at the moment I don't have access to Maple, so it would be nice if someone could re-do the graph (the code should be just a couple of lines, one could also take the data from here). Notice that being the misplaced point much bigger than in the graph, this means that the graph is going to be really flat, I guess it's OK, but another option is to leave that point out of the graph (mentioning it in the caption), or to go for a double logarithmic scale.--Sandrobt (talk) 23:12, 10 May 2016 (UTC)

Chow group and Chow ring

We have a new article titled Chow group of a stack. In the first sentence, it links to Chow group, which redirects to Chow ring. Should it be left that way, or should Chow group perhaps be a disambiguation page, or should we leave Chow group intact as a redirect while also putting a hatnote atop Chow ring telling the reader that Chow group of a stack exists, or should something else be done? Michael Hardy (talk) 20:20, 14 May 2016 (UTC)

I've been thinking this awhile: I think we should rename Chow ring to Chow group. Given the materials there, the latter name looks more appropriate. -- Taku (talk) 21:45, 14 May 2016 (UTC)

Based on your comments I'd have gone ahead and clicked on the "move" button but for this: The first sentence and maybe somewhat more of the first paragraph should get somewhat rephrased if the name is to be changed. Michael Hardy (talk) 23:18, 14 May 2016 (UTC)

The move and the necessary rewriting of the intro have been done by User:Ozob. Thanks! -- Taku (talk) 02:13, 16 May 2016 (UTC)

(To give context for the new article, given an algebraic variety/scheme X, you can define its Chow group of X, which is like homology but uses rational equivalence. If X is smooth, you can define multiplication (intersection product), giving it a ring structure and the result is called the Chow ring of X. It is probably not too important whether th article is called Chow group or Chow ring, since they are the same in the smooth context. Now, you want to extend the definition to stacks, which is straightforward over Q at least for Deligne–Mumford stack but becomes more tricky in general; i.e., one should probably not define it as simply the group of the rational equivalence classes. It is known that a DM stack with the resolution property is an (essentially) global quotient stack and so one can (in fact should ?) use equivariant Chow group in such a case. Given this background, I thought it makes sense to have a separate article, since this type of technicalities would be distracting.) -- Taku (talk) 21:52, 14 May 2016 (UTC)

I agree that Chow group is a better name. One defines individual Chow groups first (the definition is quite elementary), and then, with effort, one shows that there is a ring structure (the intersection product; depending upon how generally one wants this to be defined, this is either fairly simple or quite involved).

Oddly enough, the article mostly omits the relation to motivic cohomology, and Bloch's higher Chow groups aren't mentioned at all. That's quite a gap. Ozob (talk) 01:28, 15 May 2016 (UTC)

I've moved the page to Chow group. Ozob (talk) 18:38, 15 May 2016 (UTC)

(See above). If I'm reading the same article, I think it mentions both motivic cohomology and higher Chow group; I think the POV adopted there is that higher Chow groups are special cases of motivic homology; I don't know "how valid" this idea is. Is really so in the non-smooth cases for instance? Maybe "philosophically true"? (smooth is needed to compare with motivic cohomology). What I want for my Chrismas is motivic homology of a stack, but maybe that's too much :) -- Taku (talk) 02:13, 16 May 2016 (UTC)

(Can't stop thinking) If I remember correctly, the main difference between Bloch's higher Chow group and motivic homology is that the former relies on Bloch's moving lemma (which was controversial initially) and the latter doesn't (it uses a sheaf with transfer.) Maybe this stuff is only of historical nature. -- Taku (talk) 06:03, 16 May 2016 (UTC)

The relevant question is not how the two constructions are performed, but what they're trying to accomplish. It is generally agreed that there is a universal cohomology theory, namely the category of mixed motives. Cohomology in this category, known as motivic cohomology, is a powerful invariant. While there are several definitions of categories of mixed motives in the literature, none of them have yet been proven to behave entirely as expected. Motivic cohomology, on the other hand, has had usable foundations since Bloch. It was well-known to experts that the weight-graded pieces of algebraic K-theory captured the rational part of the motivic cohomology groups, but that's not quite the same. Bloch's groups simply worked. Bloch's construction yielded, for varieties smooth and quasi-projective over a ground field, the true motivic cohomology groups.

But they were not a panacea. If pressed for specifics, however, experts will admit that just as in the topological case, in general one has to distinguish between homology and cohomology and between compact supports and not; and in order to study the relative situation (a family of varieties over P¹ or a variety over Spec Z) one actually wants a derived category and the usual six operations. Bloch's groups did not do any of this. Voevodsky's derived category of mixed motives comes much closer. Voevodsky constructed a triangulated category in which one can find homology and cohomology with and without compact supports. If I recall correctly, at least in some cases this triangulated category is known to admit the six operations. So it is an enormous technical improvement on what Bloch did, though it came at the cost of introducing additional technique from homotopy theory. Nevertheless, it is still trying to capture the same information; despite all the new ideas, it's still aimed at the same purpose. And Bloch's definitions are still useful (even if one is willing to simply treat Voevodsky's theory as a black box) because they can be used to make direct geometric computations in some situations, whereas in Voevodsky's setup everything is defined indirectly. Ozob (talk) 13:04, 16 May 2016 (UTC)

List of Laplace transforms

The article List of Laplace transforms was recently forked out of Laplace transform. Is this really necessary and helpful to likely readers of Laplace transform? Please comment at Talk:Laplace transform#List of Laplace transforms. Sławomir Biały (talk) 12:40, 17 May 2016 (UTC)

Function theory

The page titled function theory redirected to function (mathematics). I had followed a link to that name from a new biographical article on a mathematician, in which I suspected the term has the first sense listed below. So I changed it to a disambiguation page, as follows:

See:

• Complex analysis, the study of holomorphic functions of a complex variable. Especially in works written during the 19th century and the first half of the 20th century, the term function theory often has this sense.
• Function (mathematics)

This disambiguation page lists mathematics articles associated with the same title.

Quite possibly this could benefit from more eyeballs. Michael Hardy (talk) 17:44, 18 May 2016 (UTC)

Mathematicians biographies on the drafts name space

Is there any that should be moved to the main space? Grogamoco (talk) 12:31, 15 May 2016 (UTC)

I do not know about that, but I suggest that Draft:Niggonometry be deleted as a probable hoax and intended to be offensive. JRSpriggs (talk) 14:28, 15 May 2016 (UTC)

Speedied. Cheers! bd2412 T 14:59, 15 May 2016 (UTC)

"Niggonometry" referred to "the well known 20th century mathematician CJH". When you clicked on it, you saw the article on the 19th-century English novelist Charles Dickens. If everything else in the article were not enough to conclude it's a hoax, look at that. Michael Hardy (talk) 18:17, 18 May 2016 (UTC)

Related to the same editor, is the new Fluctuation spectra (a) comprehensibly about an actual topic, and (b) not a copyvio. Sławomir Biały (talk) 23:24, 15 May 2016 (UTC)

In there I did see a draft for Boris Levin. I recognized the name as that of a well-known Soviet functional analyst. I added some references to the draft, then it was re-reviewed and moved to main-space. Nsk92 (talk) 16:09, 15 May 2016 (UTC)

What about Draft:Spyros Alexakis? He has won a respectable prize (at least I think it is), but Google Scholar citations count is very low. 187.107.38.174 (talk) 18:06, 15 May 2016 (UTC)

Actually, citations count is not so low, it's just that Google Scholar did not find some of his papers the way I made the search the first time... But, still, by citation count alone it can't be accepted, but maybe because of the prize it can. I don't know. 187.107.38.174 (talk) 18:14, 15 May 2016 (UTC)

Classical decomposition at AFD

• Additive state decomposition (AfD discussion)

You might want to weigh in on what to do, here. Uncle G (talk) 21:09, 15 May 2016 (UTC)

This article is a complete orphan, i.e. no other pages link to it. Michael Hardy (talk) 18:23, 18 May 2016 (UTC)

Користувач:Перевод

Could someone who knows more about these things have a look at this? Obviously this title is incorrect... --Randykitty (talk) 10:49, 27 May 2016 (UTC)

"Differential geometry of curves" is meant. Boris Tsirelson (talk) 10:59, 27 May 2016 (UTC)

No, that is "Диференціальна геометрія кривих" that means "differential geometry of curves". By the way, looking on the history, it appears that the article is a (very bad) translation of the Russian WP article on the subject (probably an automatic translation). I have no idea of the meaning of the title. IMO this translation does not add anything useful to the content of Differential geometry of curves. Therefore, I suggest deletion. D.Lazard (talk) 11:12, 27 May 2016 (UTC)

(e/c) Differential geometry of curves already exists. There does not seem to be anything there that is not already covered in our existing article, apart from some material on curvature which is already covered in the curvature article. Moreover, the mistitled article looks like the result of a bad machine translation. I don't think anyone would lose sleep if this article were just deleted. I will add a prod tag, but feel free to remove it as per the usual WP:PROD rules. Sławomir Biały (talk) 11:14, 27 May 2016 (UTC)

Matrix decomposition into clans

Is there any content worth saving in Matrix decomposition into clans? —David Eppstein (talk) 05:28, 28 May 2016 (UTC)

On one hand, the author talks of solving linear systems over rings and monoids. We have an article Linear equation over a ring that covers some of the basics. But rather than a general monoid, what the author really seems to be discussing is a solution technique for solving a system of linear Diophantine equations over nonnegative integers, nonnegative integers being a simple type of monoid. For this, we already have Diophantine equation#System of linear Diophantine equations. The section doesn't discuss the nonnegative constraint, but there exists other papers out there, such as [16], which treat this common case in integer programming. The author's papers, while interesting, don't seem to have generated any secondary commentary or citations. Hence this work is non-notable and I don't think it would be of due weight to include it in Diophantine equation#System of linear Diophantine equations. In short, no content worth saving. --Mark viking (talk) 18:40, 29 May 2016 (UTC)

Ok, thanks; I've prodded it. Another of the same editor's contributions, about another piece of research by the same author (who is likely the same person as the editor) is also prodded: see Zaitsev neighborhood. —David Eppstein (talk) 19:21, 29 May 2016 (UTC)

John von Neumann GA review

John von Neumann is being reviewed as a potential Good Article. Please participate in the review at Talk:John von Neumann/GA1. —David Eppstein (talk) 16:52, 25 May 2016 (UTC)

I nominated the article under Military History because we're the ones who polished the article to bring it to GA, as part of a broader effort on Manhattan Project people, and our project is a multi-disciplinary one. Assistance is welcome. Hawkeye7 (talk) 22:03, 25 May 2016 (UTC)

The article has now passed its GA review. If WP-Mathematics has an A class Review process, it can nominated. Hawkeye7 (talk) 22:25, 28 May 2016 (UTC)

I think the WPM A-class process is defunct. —David Eppstein (talk) 22:52, 28 May 2016 (UTC)

Oh. It has nowhere to go then. I could nominate it for A class at MilHist, but there doesn't seem much point. Hawkeye7 (talk) 01:11, 29 May 2016 (UTC)

In my dream, all mathematicians from http://fabpedigree.com/james/gmat200.htm have featured articles here on Wikipedia. :D 189.6.194.219 (talk) 16:26, 30 May 2016 (UTC)

Advanced calculus

I occasionally see the phrase "advanced calculus". Sometimes it seems to mean introductory real analysis (e.g., sequences, continuity, what distinguishes the reals from the rationals) and sometimes it seems to mean topics in calculus that are usually introduced later rather than earlier in a sequence of calculus courses (e.g., trig substitution, multivariate calculus). Right now, Advanced calculus is a red link. What should we do with it? My first thought is to redirect it to Real analysis. —Kodiologist (t) 15:59, 30 May 2016 (UTC)

I think this terminology is more social than mathematical. I don't know in other countries, but here in Brazil, calculus courses are very different from analysis courses. In calculus one is more interested in the theorems and intuitions than in their rigorous algebraic, topological, number theoretic, etc... justifications. Maybe Advanced calculus could be a redirect to Calculus on manifolds? 189.6.194.219 (talk) 16:20, 30 May 2016 (UTC)

As said in the second paragraph of Calculus, calculus is essentially the elementary part of mathematical analysis. Therefore, this is the natural target for a redirect. I'll create the redirect. Calculus on manifolds is a dab page and is thus not a correct target for a redirect. D.Lazard (talk) 16:30, 30 May 2016 (UTC)

I once taught a course called "advanced calculus for engineers", consisting of topics needed as prerequistes to a fluid dynamics course, and about half of it was complex analysis, so "real analysis" might not be a perfect target for a redirect. Michael Hardy (talk) 18:00, 30 May 2016 (UTC)

In the spirit of Wikipedia:Verifiability, I took a peek at amazon.com's titles "Advanced Calculus". There is wide variety: everything from multivariable calculus and calculus on manifolds to Fourier series and topological vector spaces. Mgnbar (talk) 18:17, 30 May 2016 (UTC)

Jun 2016

Garden of Eden (cellular automaton)

I'm having a disagreement with an anonymous editor over the preferred level of technicality and redundancy in the lead section and lead sentence of Garden of Eden (cellular automaton). Third opinions welcome; see article history for alternative versions and Talk:Garden of Eden (cellular automaton) for discussion. —David Eppstein (talk) 23:54, 29 May 2016 (UTC)

I don't want to take part in this, but I've found your (Eppstein's) favorite version much better. The other one is just too hard even for mathematics students, imagine for laymen to understand... 189.6.194.219 (talk) 16:24, 30 May 2016 (UTC)

This has now progressed to an RfC. --JBL (talk) 14:31, 1 June 2016 (UTC)

pertinence of the article Gonit Sora

I wonder about the pertinence of the following article: Gonit Sora. I just removed a link which didn't add something to Évariste Galois. I wonder if it is not kind of spam. Xavier Combelle (talk) 11:26, 2 June 2016 (UTC)

"established"?

The article titled Durand–Kerner method begins like this:

In numerical analysis, the Durand–Kerner method, established 1960–66 and named after E. Durand and Immo Kerner, also called the method of Weierstrass, established 1859–91 and named after Karl Weierstrass, is a root-finding algorithm for solving polynomial equations. In other words, the method can be used to solve numerically the equation

ƒ(x) = 0

where ƒ is a given polynomial, which can be taken to be scaled so that the leading coefficient is 1.

What in the world does "established" mean? The method was "established 1960–66", but when known by a different name it was "established 1859–91. Michael Hardy (talk) 17:56, 30 May 2016 (UTC)

IMO, "established" means here "introduced". In French, "etablir" (French word for "to establish") is sometimes used for "to prove". D.Lazard (talk) 18:24, 30 May 2016 (UTC)

But why was it introduced at different times when known (today) by different names? Michael Hardy (talk) 21:03, 4 June 2016 (UTC)

This language is definitely confusing: established often means 'proved,' but that substitution makes the lead confusing - why did it take 30 years to 'establish' it the first time, and why was it 'established' again several decades later? Also, one does not generally prove a method (although one might prove that it works), as far as I know. Someone who actually knows something about this method should check this out. Nat2 (talk) 02:57, 5 June 2016 (UTC)

I found a book by Petkovic that clarifies the history. The method was discovered by Weierstrass and rediscovered independently by Durand and Kerner. I've updated the lead with the information. --Mark viking (talk) 03:46, 5 June 2016 (UTC)

MathML now the default

The move to make the client side SVG rendering the default is now live on the English Wikipedia. This is task T131177 billed as "MathML now the default" but I don't think MathML is actually used even on firefox.

I'm currently getting lots of bugs when editing. The only way I can resolve these is to switch my preference to PNG mode save my preferences. Then you can switch the preference back to "MathML with SVG or PNG fallback" mode and things work fine again.--Salix alba (talk): 21:47, 31 May 2016 (UTC)

It looks good. Have they fixed the Firefox incompatibility? Or was that smuggled into a Firefox update? Sławomir Biały (talk) 22:10, 31 May 2016 (UTC)

MathML is a slight misnomer. The MathML is still embedded in each page, but is not actually displayed. What you're really seeing is server-side rendered SVG (on Firefox, at least). Previously you did get real (but broken) MathML on Firefox. SVG seems to be an improvement in some respects (math scales better with the rest of the text compared to PNG) and a regression in others (font weight is a bit too heavy for my taste). —Ruud 22:24, 31 May 2016 (UTC)

We ${\it {have}}$ working ${\bf {baselines}}$!!!!! Hooray!!!!! ${\bf {Years{\rm {\ of}}}}$ waiting and ${\it {our\ {\bf {wish}}}}$ has been ${\bf {granted!!!!!}}$ Many thanks ${\rm {to}}$ everyone ${\it {who}}$ made this $a\ {\mathit {r}}eality!!!!!$ Ozob (talk) 01:43, 1 June 2016 (UTC)

I appreciate your enthusiasm, but your prose has four Failed to parse errors in my browser :-) Windows 10, latest Chrome, PNG images mode. --Mark viking (talk) 03:39, 1 June 2016 (UTC)

It's still not the case that ${\text{text inside math templates}}$ matches article text in font, font size, or crispness. Also for me the <math>\it baselines are lower than the other fonts. But it is at least an improvement over the bitmaps. —David Eppstein (talk) 04:11, 1 June 2016 (UTC)

@Mark viking: That would be a cache error, per the bug in question. :) --Izno (talk) 11:18, 1 June 2016 (UTC)

Copying and pasting:

We \it have working Failed to parse (syntax error): \bf baselines !!!!! Hooray!!!!! Failed to parse (syntax error): \bf Years \rm\ of waiting and Failed to parse (syntax error): \it our\ \bf wish has been Failed to parse (syntax error): \bf granted!!!!! Many thanks \rm to everyone \it who made this a\ \mathit reality!!!!!

Michael Hardy (talk) 18:28, 5 June 2016 (UTC)

If anyone using Firefox wants to get real MathML back again you can reenable the MathML with a bit of CSS

.mwe-math-fallback-image-inline {
	display: none !important;
}

.mwe-math-mathml-a11y {
		display:inherit;
		position: inherit;
		clip:inherit;
		width:inherit;
		height:inherit;
		opacity:inherit
}

Add this to your Special:MyPage/vector.css and the MathML will reappear.--Salix alba (talk): 16:55, 2 June 2016 (UTC)

Having just gone through this, a better and easier fix is to install two Firefox extensions: Native MathML and MathML-fonts. Better because it also gives you fonts that will improve the appearance, and it works on all sites, not just WP. The Native MathML extension is a bit of a misnomer. It does not implement MathML, just convinces Firefox to use it when it's available.

Although the appearance is much improved, the new behavior is a bit of a regression, as you now have to install stuff to get good looking math. We don't seem to have much control over this situation. I do think the documentation could be improved. If you click on "Help" in the WP preferences page, it takes you to this Mediawiki help page, which is not very helpful. It talks about Extension:Math, which will only confuse WP users because it's a server side extension that casual users have no control over. Only by clicking on that link will the user finally be taken to Extension:Math, where they can learn they are "required to install the Native MathML extension and math fonts."

If anyone is in a position to improve the documentation, I think that would be a good thing. Better yet would be if browser display of math would just work without users having to do anything. I don't consider fallback svg acceptable, but maybe that's just me. Kendall-K1 (talk) 14:42, 3 June 2016 (UTC)

I think there is a case for a MathML option which actually displays the MathML. It worth bringing this up at T131177. --Salix alba (talk): 15:54, 3 June 2016 (UTC)

Flaw in Euclidean algorithm graphic

A graphical expression of Euclid's algorithm to find the greatest common divisor for 1599 and 650.

 1599 = 650×2 + 299
 650 = 299×2 + 52
 299 = 52×5 + 39
 52 = 39×1 + 13
 39 = 13×3 + 0

Algorithm#Euclid.E2.80.99s_algorithm

This graphic shows 650 subtracted from 1599 twice to leave a remainder of 299.
It does not show 299 subtracted twice from 650 to get 52.
It shows 52 subtracted five times from 299 to get 39.
It does not show 39 subtracted from 52 to get 13.
Shouldn't those omissions be remedied?

Michael Hardy (talk) 18:14, 5 June 2016 (UTC)

Does anyone have recommendations for good tools to produce this sort of graphic? —David Eppstein (talk) 19:58, 7 June 2016 (UTC)

Gimp can do this; frames are layers.[17]. Or if you prefer a CLI, gifsicle [18] can paste a list of gifs together into an animated gif. --Mark viking (talk) 20:40, 7 June 2016 (UTC)

Index of The Educational Times

Is there one? I see a few scattered refs pointing to various math questions posed in this journal (and the companion/offshoot Mathematical Questions with Their Solutions). The latest information I can find is a 1992 article about these journals (doi:10.1016/0315-0860(92)90057-I) saying there was at most an index published within a few certain volumes. DMacks (talk) 18:55, 7 June 2016 (UTC)

I don't know about an index, but most of the individual issues can be browsed at http://ioearc.da.ulcc.ac.uk/view/organisations/edtimes.html

The Internet Archive also has quite a lot of the spin-off series, "Mathematical Questions": https://archive.org/search.php?query=mathematical+questions&page=1

As the paper by Ivor Grattan-Guinness that you cited says, in all there were some 20,000 pages published, devoted to 19,000 problems; there was apparently no index as of 1992. Jheald (talk) 21:08, 7 June 2016 (UTC)

This 2003 paper gives a bit more on the background to the journal doi:10.1016/S0315-0860(03)00026-0; this UCL page gives a bit more about the institution behind it, the intriguingly named College of Preceptors. According to this archive catalogue entry from the IoE, the "majority of the volumes are indexed" -- though I haven't looked to see to what level of informativeness. Jheald (talk) 21:14, 7 June 2016 (UTC)

Egomath

An article of possible interest to others here--Egomath, a mathematical search engine for Wikipedia--has been proposed for deletion. --Mark viking (talk) 18:53, 8 June 2016 (UTC)

Milne-Thompson method for finding an analytic function

If anyone knows anything about the Milne-Thompson method for finding an analytic function, such as (1) whether the article ought to exist, or (2) what more it should say, or (3) references to cite, etc., then there it is. (I found it badly in need of copy-editing and did some of that, but probably more of that can be done.) Note: "Milne-Thompson" is a hyphenated name of one person, _not_ two names; hence it is properly a hyphen rather than an en-dash. Michael Hardy (talk) 19:06, 21 May 2016 (UTC)

I don't know the answers to your questions, but it's about holomorphic functions, not analytic ones, so I changed the title to Milne-Thompson method for finding a holomorphic function. Ozob (talk) 19:16, 21 May 2016 (UTC)

It seems that the correct spelling of the name is "Milne-Thomson", with no p, so I've moved the page (again) to Milne-Thomson method for finding a holomorphic function. Ozob (talk) 02:02, 22 May 2016 (UTC)

There should be no problem in finding secondary sources. The name the thing seems to be actually used for it. (If Google finds it, then it must be notable, right?) YohanN7 (talk) 12:45, 9 June 2016 (UTC)

User:Mathbot is going to break

User:Mathbot is going to break soon, because of changes to the API. The bot owner doesn't seem to edit very often. If anyone is interested in this, please see the latest discussion at WP:BOTN. Whatamidoing (WMF) (talk) 01:10, 10 June 2016 (UTC)

Oleg claims that he just fixed it (time will tell). See User talk:Oleg Alexandrov#API change will break your bot. JRSpriggs (talk) 06:28, 10 June 2016 (UTC)

Does the word "perfect", in the phrase "perfect sphere", mean anything?

Redzemp insists on replacing "sphere" by "perfect sphere" in the mathematics article spheroid. My position is that this is meaningless verbosity, like talking about "wet water". Please discuss at Talk:Spheroid if you have an opinion on this. —David Eppstein (talk) 21:46, 9 June 2016 (UTC)

This is what I wrote on his talk page:

hi. I don't like genuine redundancy either, but frankly you're just plain wrong with your comparisons of "wet water" and other things to the phrase "perfectly spherical". Astronomers and degreed people themselves have used that phrase. People who would never say the phrase "wet water". Not all spheres are necessarily perfect, is the point. What's the problem here?? And as I said, other WP articles have used that phrasing, as well as outside Reliable Sources. From another Wikipedia article that I had nothing to do with, these exact words:

"The Earth is not perfectly spherical but an oblate spheroid, so the length of a minute of latitude increases by 1% from the equator to the poles. Using the WGS84 ellipsoid, the commonly accepted Earth model for many purposes today, one minute of latitude at the WGS84 equator is 6,046 feet and at the poles is 6,107.5 feet. The average is about 6,076 feet (about 1,852 metres or 1.15 statute miles)."

And from an article on physics.stackexchange.com, these words:

"By this measure, the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths, which means that its polar diameter differs from its equatorial diameter by only 10 kilometres (6.2 mi)."

Are these scientists being "redundantly redundant" as you put it? Or do you see them saying "wet water"? (And that's just some examples; there are a lot more.) You accused me of "edit-warring" for simply not putting up with rude unwarranted reverts, for excuses that simply don't hold up, and keeping to 3RR. (One of my comments on the page was just an edit comment with no real edit...so I kept right at 3RR, and won't cross that.) YOU are edit-warring by imposing and removing a valid mod (provably valid mod), and clarity, that is NOT really "redundant"...as I kind of just proved with just a sample of places that rightly use the phrase that you have an issue against. The edit and qualifier was for clarity and is correct and used phrasing, and does not qualify for abrupt removal on the grounds of "redundant". That might be true if all "spheres" were considered always "perfect". Apparently not all of them are. Redzemp (talk) 21:22, 9 June 2016 (UTC)

end of statement...

It's clear that to compare "perfectly spherical" or 'perfect sphere' with the phrase "wet water" is simply wrong and ignorant, and counter-factual...and not applicable. The phrase in question is not "spherical sphere" (THAT would be "redundant") but rather the phrase that you keep removing is "perfectly spherical" or "perfect sphere", and sorry, that simply is not redundant...as sources etc prove. Not all spheres are necessarily "perfect" is the obvious and the stated and referenced point. Redzemp (talk) 22:18, 9 June 2016 (UTC)

While this discussion should be on Talk:Spheroid perhaps placing it here will generate a greater response and may point to a larger issue that is of interest to the project. First of all, a sphere is a sphere is a sphere. A non-perfect sphere is not a sphere, so the adjective is mathematically redundant. However, to the general populace, the term sphere may refer to anything that is almost spherical (technically a spheroid) and for those who incorporate this fudge factor in their terminology, a perfect sphere distinguishes a mathematical sphere from the misnamed spheroids. The issue, as I see it, is whether or not a page that is devoted to the mathematical presentation should strictly use mathematical terminology even though the audience may not appreciate the mathematical nuances. I see the current (endless) discussion going on at Talk:Area of a disk as being essentially the same issue in a slightly different context. As an editor with a mathematical background, I do see, in myself, a definite bias towards precise, correct mathematical terminology ... but I do see this as a bias and feel that in some articles I should loosen up and not try to be as exact as I normally would desire to be. Bill Cherowitzo (talk) 03:51, 10 June 2016 (UTC)

Thank you, Bill. And this is what I wrote on David's talk page where we were having a discussion regarding this, about this "mathematics article" argument, right below:

In "mathematics" or any other context, would you call the sun a "sphere" then? Even if it's not "perfect"? Would you call the earth a "sphere" even though it's not a perfect sphere? The sun and earth are both spheres, though "near perfect" or "not perfect". Why are they called "sphere" even if not 100% "perfect" in absolute circularity in every part? Yes we call the earth a "spherOID" but isn't the earth also called a sphere too? Maybe not in strict mathematics, I guess is your point. My point is that even you'd have to admit that the phrase "spherical sphere" is WAY MORE "redundant" than "perfectly spherical" or "perfect sphere". Remember, Wikipedia is NOT JUST for technical experts and semantical types, but also for average readers who may need elaboration and clarity. Again, OTHER Wikipedia articles dealing with distances etc, regarding the earth, say phrases like "perfectly spherical" etc... And so do some outside sources...written by degreed scientists. My point is that the phrase "perfectly spherical" is PROVABLY NOT the same as "wet water", as you were saying, with that comparison. The phrase "spherical sphere" would be more comparable to "wet water". As both those phrases are truly redundant and needless. Redzemp (talk) 22:36, 9 June 2016 (UTC)

and also...

Here's the problem. I disagree with you in thinking that this article is strictly narrowly just a "mathematics article" in every single line or paragraph. And the context of the immediate paragraph and sentences in here were dealing with astronomy matters, the planet earth. (Even that means what, since isn't the whole universe mathematical in various ways anyway?) You say that this article is not about "astronomy". (As if astronomy has no math in it, which we all know that that's not true). But even so, how can you say that the Spheroid article is ONLY a "mathematics article" in every single line, sentence, or paragraph... when a paragraph about the PLANET EARTH (an astronomical thing) is in the article, etc? And also "gravity". Which also includes physics. All are connected. Such as: "Because of the combined effects of gravity and rotation, the Earth's shape is not quite a perfect sphere but instead is slightly flattened in the direction of its axis of rotation. For that reason, in cartography the Earth is often approximated by an oblate spheroid instead of a sphere. The current World Geodetic System model uses a spheroid whose radius is 6,378.137 km at the equator and 6,356.752 km at the poles." (And sorry, the sun and earth are "spheres" broadly, and are called that by scientists, when not being so overly-technical, and use the phrase "near perfect sphere" or "not a perfect sphere" etc. Both the sun and earth (and the moon too) are circular objects, even if not perfectly so on every side necessarily. Why does the word "spheroid" have the very word "sphere" in it? But anyway, you see the paragraph's wording dealing with astronomy matters. So even if this article is maybe mainly a "mathematics article", it's not 100% strictly just that. At least not totally in this paragraph in question. Redzemp (talk) 22:53, 9 June 2016 (UTC)

The "earth" paragraph in the "Spheroid" article is obviously not strictly a "mathematics article" point and drift there. And even if mathematically a "sphere" is always perfect, in other aspects, in broad usage, not necessarily, all the time. Regards. Redzemp (talk) 15:37, 10 June 2016 (UTC)

Even in mathematics, we sometimes distinguish topological spheres from the round sphere. I have no opinion on whether "perfect sphere" is an appropriate neologism. Sławomir
Biały 15:55, 10 June 2016 (UTC)

Families of polynomials

I've found a number of very brief articles on families of polynomials

• Dual q-Hahn polynomials
• Affine q-Krawtchouk polynomials
• Quantum q-Krawtchouk polynomials
• Q-Meixner polynomials
• Q-Meixner–Pollaczek polynomials
• Continuous dual q-Hahn polynomials
• Continuous big q-Hermite polynomials
• Q-Krawtchouk polynomials
• Continuous q-Hermite polynomials

and probably a few more. They are all very brief, barely more than just references, and don't even have a definitions instead they have empty formulas which are causing parsing error. I'm not sure if they are notable enough and I've prodded the first. --Salix alba (talk): 16:19, 9 June 2016 (UTC)

Some of these certainly deserve articles, and the current versions are not exactly worthless (they do have lists of references, after all), but also obviously they are not acceptable in their current form. --JBL (talk) 20:20, 9 June 2016 (UTC)

I think this class of articles was created by R.e.b. for orthogonal polynomials in the hypergeometric Askey scheme of classification. They all have the same set of general references, which are sufficient for verifiability. One approach would be to stubify these by removing the empty sections and possibly the animated plots. In some cases, we'd be left with a short description and references for more information--still useful for our readers. Another approach might be to merge members of each O.P. family together, for instance, Continuous dual Hahn, Continuous Hahn, Hahn, dual Hahn, Continuous dual q-Hahn, Continuous q-Hahn, q-Hahn, and dual q-Hahn into one conglomerate Hahn article. Stubify is the quick solution, perhaps with merges later. --Mark viking (talk) 21:22, 9 June 2016 (UTC)

There is now an AFD on the subject Wikipedia:Articles for deletion/Dual q-Hahn polynomials (2nd nomination).--Salix alba (talk): 15:11, 12 June 2016 (UTC)

How about an aggregation article called Families of polynomials, which would doubly serve as a chart of the classification hierarchy? Most of these articles are an equation, a classification, a who-and-when, and a reference. Still images can stay, while animations can be linked into a commons gallery. Famous polynomials can have similarly short blurbs while linking to the main article. SamuelRiv (talk) 00:34, 13 June 2016 (UTC)

Lebesgue integral

There is some discussion at Talk:Integral on whether the standard intuitive idea that the Lebesgue integral proceeds by "partitioning the range" of a function is indeed correct and helpful to the reader. I am unclear what the specific objection to this content is, but I think it would benefit from a third opinion. Sławomir Biały (talk) 10:19, 21 June 2016 (UTC)

Divisions of mathematics

In the Template:Areas of mathematics, the "Divisions" are listed as: Pure, Applied, Discrete, Computational, Meta-, and Recreational. I am not sure this is helpful or accurate. For instance, it elevates Recreational mathematics to one of 6 presumptively equal divisions of the whole field of mathematics–an interesting but possibly unbalanced characterization. Below is WP's assessment of the six associated "division summary" articles along with my comments.

division	Wikipedia's rating	my assessment
Pure mathematics	B Class Top Importance	well written
Applied mathematics	B Class Top Importance	well written
Discrete mathematics	B Class Top Importance	well written but overlaps the other so-called divisions
Computational mathematics	unrated	needs a lot of work; more a list than the summary of a division
Meta-mathematics	C Class Top Importance	fairly well written but needs more work
Recreational mathematics	Start Class Low Importance	not well organized or written–but should be Medium importance

I would eventually like to bring a little more consistency to all of these articles. Are they really a fair overview of all of mathematics? I am not qualified to say. I had a brief discussion about all this with WP editor and mathematician Bill Cherowitzo who said:

One problem with these divisions of mathematics is that they do not form a partition of the field. For example, I am a pure mathematician, doing discrete mathematics with some very computationally intense periods in my work, and (formerly) in an applied math department. Some of my work could be considered to be recreational, or at least that is the way I present it to non-mathematicians and I definitely think that meta-mathematics is a branch of logic and has nothing to do with mathematics. I look at these divisions ... and laugh!

What makes something a mathematical recreation versus a serious mathematical topic is pretty much a matter of taste. For instance, J.J. Seidel contributed a chapter on combinatorial designs to W.W. Rouse Ball's Mathematical Recreations and Essays, but I've spent most of my career seriously studying these things. Latin squares at the level of Sudoku and Ken-Ken are clearly recreational, but the existence of sets of mutually orthogonal ones quickly turns into cutting edge mathematical research. Where do you draw the line?

I am particularly interested in improving the article Recreational mathematics and would welcome some collaboration.--Toploftical (talk) 17:27, 13 June 2016 (UTC)

I've been complaining about a similar problem at Talk:Mathematics for years. The problem, as Bill Cherowitzo points out, is that these categorizations are cultural and social, not formal or technical. They're messy. They overlap and underlap. It's hard to get agreement about which obviously-defective categorization is to be preferred over the others. Mgnbar (talk) 17:48, 13 June 2016 (UTC)

Exactly; that's why we should strain to avoid implying that any of these characterizations is to be taken too seriously. I worry that putting them into templates and categories has the danger of implying that they should be taken more seriously than they actually deserve. --Trovatore (talk) 18:12, 13 June 2016 (UTC)

By the way, my obviously defective, but surprisingly accurate, rule of thumb for what constitutes "recreational mathematics" is "anything that depends on a choice of radix". Certainly, it doesn't capture everything (flexahexagons don't depend on a choice of radix but seem like recreational math), and I wouldn't want to declare once and for all that something depending on a choice of radix must be recreational math. Still, it does a pretty good job. --Trovatore (talk) 18:15, 13 June 2016 (UTC)

Also, it excludes normal numbers. Besides their interest in number theory (an interest which I agree tends towards recreational) they have connections to probability and theoretical computer science. See normal number#Connection to finite-state machines. Ozob (talk) 20:04, 13 June 2016 (UTC)

Normal numbers don't depend on a choice of radix. --Trovatore (talk) 20:06, 13 June 2016 (UTC)

It is a theorem of Schmidt, cited in the article, that if r and s are such that rⁿ ≠ s^m for any integer n and m, then there is a continuum of numbers normal in base r which are not normal in base s. Ozob (talk) 20:23, 13 June 2016 (UTC)

That quantifies over all possible radices, and therefore does not involve the choice of a radix. --Trovatore (talk) 21:00, 13 June 2016 (UTC)

r and s are fixed; there is no quantification over radixes. So, for example, the theorem says there are a continuum of numbers normal in base 10 which are not normal in base 2. Ozob (talk) 21:50, 13 June 2016 (UTC)

I admit my language was not as precise as it could have been, but do you really not understand what I mean? r and s are "fixed", but the theorem quantifies over them. There is no particular base being singled out here.

Recreational math, on the other hand, is often specific to base 10. Or occasionally to base 12, or some other particular base. That is what triggers my rule of thumb. --Trovatore (talk) 22:00, 13 June 2016 (UTC)

I really did not understand what you meant. Schmidt's theorem, more formally, is $r\in \mathbf {Z} _{+}\land s\in \mathbf {Z} _{+}\land \lnot (\exists n\exists m\,r^{n}=s^{m})\Rightarrow \exists S\subseteq [0,1]...$, where the omitted part expresses the fact that S has the cardinality of the continuum and that numbers in S are normal with respect to r but not s. No quantification over r or s is necessary in this statement, whence our misunderstanding. Nevertheless, I believe I grasp your meaning now. Ozob (talk) 22:10, 13 June 2016 (UTC)

There is an implicit $\forall r\forall s$ in front of that statement, which is the quantification over r and s to which I referred. Anyway I'm glad we understand each other now. --Trovatore (talk) 22:19, 13 June 2016 (UTC)

For another example of base-specific but serious mathematics, see Bailey–Borwein–Plouffe formula. —David Eppstein (talk) 21:56, 13 June 2016 (UTC)

Yes, this is at least arguably an exception. --Trovatore (talk) 22:02, 13 June 2016 (UTC)

I propose that the so-called six divisions of mathematics in the Template:Areas of mathematics simply be removed. What purpose do they serve? Moreover, the "divisions" characterization suggests that they are the 6 nodes of a tree of further subdivisions. But no such further branching occurs on the associated summary pages. I totally agree with Cherowitzo that meta-mathematics is a branch of logic. And I would simply demote recreational mathematics to one of the "areas" of math. How to characterize Pure and Applied math is harder to say.--18:59, 13 June 2016 (UTC)

It's not clear why being a branch of logic should exclude also being a branch of mathematics.

That said, I'm not necessarily opposed to removing the divisions, or indeed the whole template. But if the "areas" are thought to be useful, then the "divisions" are arguably useful with the similar rationale. --Trovatore (talk) 19:11, 13 June 2016 (UTC)

(If the "divisions" are kept, I would propose replacing "metamathematics" by "mathematical logic", which is a more general area of study, clearly part of mathematics, and not otherwise clearly represented in any of the other divisions.) --Trovatore (talk) 19:15, 13 June 2016 (UTC) Oh, except that I suppose it's part of "pure". Right, I hadn't really noticed that — the "pure" and "applied" parts are really kind of a different level of categorization than the other four; "pure" and "applied" pretty much subsumes all of mathematics, albeit with overlap. That is a different kettle of fish. Maybe the best solution is indeed to remove the "divisions" (or, again, the whole template). --Trovatore (talk) 19:19, 13 June 2016 (UTC)

Everybody should have a look at Template talk:Areas of mathematics. There are some good suggestions there. Other people have been troubled by the current contents of the template. As a temporary experiment, I am going to demote Recreational Mathematics to one of the "areas". Whatever it is, it is not one of the major divisions of math.--Toploftical (talk) 17:44, 19 June 2016 (UTC)

I think the 2010 proposal by Kiefer.Wolfowitz (who has been banned) is better than the current revision, since at least it provides some backbone for navigation. However, this template is inherently problematic, since it is not based on any reasonably verifiable division of the mathematical sciences. If we are to insist on having a navigation template at all, then it should be based on a clear division of mathematics, such as the Mathematics Subject Classification. Sławomir Biały (talk) 12:18, 20 June 2016 (UTC)

I agree, with one proviso: It is easy to find a verifiable division of the mathematical sciences. All we need is a published source that attempts to partition all of mathematics in some way. The MSC does this, as do the ICM program and the Library of Congress subject catalog. The problem for us is that, as mathematicians, we're used to proof; but an organizational question like this one is more akin to library science. Asking for the classification to be correct is asking the wrong question. We should ask for it to be useful. Ozob (talk) 12:45, 20 June 2016 (UTC)

Toploftical here: I completely agree with User:Ozob

By ICM I assume you mean the International Congress of Mathematicians. Can someone provide a link to their classification system? (For the Kiefer.Wolfowitz proposals see here.) I strongly feel that somebody should reorganize things along the lines they suggest. Meanwhile I will simply list a few anomalies I have noticed to emphasize how the whole math template system is not very well though out.

• There are templates for Algebra (but not Geometry), Calculus (but not Analysis), Number theory, Functional analysis, Game theory, Tensors (but not Linear algebra), Computer science, Statistics, Set theory, and Topology–and none of the other "areas". It all seems a bit ad hoc.
• The article Areas of mathematics has almost nothing in common with the Template:Areas of mathematics and the template Areas of mathematics has little in common with the article Mathematics Subject Classification. Then there is the independent Lists of mathematics topics.
• Shouldn't Boolean algebra be included in either the template Areas of mathematics or template Algebra?
• Areas of mathematics does not mention Category theory (oh, I now notice that it is in the Algebra template).

If somebody wants to take on the daunting task of reorganizing the templates along the lines Ozob suggests, I will support them and even do some of the work.--Toploftical (talk) 09:40, 22 June 2016 (UTC)

For the ICM program structure, see [19]. Ozob (talk) 12:28, 22 June 2016 (UTC)

Re the earlier question about how to categorize recreational mathematics: although I doubt there is much ICM activity on this topic, it seems to fit well under "19. Mathematics education and popularization of mathematics". I don't see where order theory fits, though. —David Eppstein (talk) 13:54, 22 June 2016 (UTC)

Category:Pages with math errors

There now a new tracking category Category:Pages with math errors which list all pages which have a mathematical syntax error in their formula. It might be worth having an occasional glance at. I think this relates to T49037. For many pages the errors can be fixed by simply doing a WP:PURGE on the page. --Salix alba (talk): 21:14, 22 June 2016 (UTC)

Merely saying that there is a mathematics error on a page without being more specific about where on the page (which formula) is not likely to be very helpful. JRSpriggs (talk) 21:26, 22 June 2016 (UTC)

To clarify this lists pages when the <math> tag failed to parse due to syntax errors, rather than equations which wrong. They are generally pretty easy to find as soon as you look at the page, with large red error messages.--Salix alba (talk): 21:53, 22 June 2016 (UTC)

This seems to be gerrit:292576 from phab:T134872. Oliv0 (talk) 13:13, 23 June 2016 (UTC)

Adrian Dudek

SPA Drriemann (talk · contribs · deleted contribs · logs · filter log · block user · block log) has been adding references to Adrian Dudek to various number theory articles. These appear to be primary sources, rather than secondary sources, and some are self-published (on arxiv). Are any worth keeping? Sławomir Biały (talk) 14:23, 24 June 2016 (UTC)

I've removed all the references, but feel free to restore any if you think they're appropriate. Sławomir Biały (talk) 14:58, 24 June 2016 (UTC)

Universal trinity

A new article titled Universal trinity bears the "mathematical logic" category tag. It looks like either an attempt to do theology via mathematical logic or a use of mathematical logic as a metaphor in theology. I suspect it constitutes "original research" as defined by WP:OR. I have proposed its deletion and notified its creator. If the creator of the article deletes the "prod" tag, I'll take it to AfD unless someone beats me to it. Michael Hardy (talk) 23:55, 20 June 2016 (UTC)

I just added an additional source which fully clarifies the triplicities between the branches in the 12 positions, but this was already pretty clear due to the listed Category:Astrological triplicities? Are the listed sources about a very basic and universal view to the trinity or is rather this view itself not ok for you? --MathLine (talk) 20:09, 22 June 2016 (UTC)

Not only are religion and astrology both absurd, but most Christians regard astrology as false and sinful. JRSpriggs (talk) 21:31, 22 June 2016 (UTC)

The issue is that the article does not appear to meet Wikipedia's guidelines for inclusion. The article appears to be original research, and original research is not permitted on Wikipedia. Even if it is not original research, the article is written improperly. It does not seem to have appropriate citations to reliable sources, and it may not adhere to a neutral point of view. You might want to model your article on the astrology article. Ozob (talk) 00:48, 23 June 2016 (UTC)

Actually there is no statement in this article which fundamentally lacks sources and to reproach even personal bias in a so general disquisition is absurd. Even mathematicians who worked their whole lifes only within plain mathematics keep a sense of Category:Philosophy of mathematics which makes clear that there are other reasons for your tunnel view here! MathLine (talk) 14:24, 23 June 2016 (UTC)

Agree, the article should be deleted. The sources for the first sentence are an entire book, without a specific page number, and a website which does not mention conjectures, etc. That first sentence is not an anomaly: most of the sources do not directly support the content. The article is obvious, unsalvageable WP:OR. I strongly suspect it is entirely a WP:HOAX, and potentially speediable for that reason. Sławomir Biały (talk) 19:33, 23 June 2016 (UTC)

The article has been deleted as a blatant hoax. Sławomir Biały (talk) 12:39, 24 June 2016 (UTC)

At least the term "Universal trinity" is used also in further sources like http://www.wisdomworld.org/setting/trinity.html, http://dharmarepublic.com/trisula/ so if the listed sources have been so extremely imprecise then maybe we could abide the determined 7 day discussion time to correct them? A move into my namespace for that purpose was also not considered? MathLine (talk) 16:34, 24 June 2016 (UTC)

I think you misunderstand what type of sources are needed here for this article (but also in general) are scholarly articles in science journals, books by established academics (with page numbers) and websites of established mathematicians, at math or science institutes, MacTutor or Mathworld. So far almost all sources used or suggested including the two you've just mentioned fail that standard. As long as we do not have at least some sources of that type, there is no place in WP for such an article. There is no point in moving it into your namespace as long as that type of source is not available (at all).--Kmhkmh (talk) 16:53, 24 June 2016 (UTC)

Read WP:BIASED and learn that of course not only directly university related sources are acceptable!! The mentioned source from wisdomworld.org refers to the in theosophy appreciated source THEOSOPHY, Vol. 45, No. 7 and its headline (!) is "THE UNIVERSAL TRINITY". If you have a problem with the listed Category:Mathematical logic then that LINE could be deleted. Besides this WikiProject Mathematics I also involved Wikipedia talk:WikiProject Astrology#Academic mathematics vs. astrology in Universal trinity (before its deletion) and apparently it seems also necessary with Wikipedia talk:WikiProject Theology which seems to cover also theosophy but for that it should be at least restored in the namespace, right? --MathLine (talk) 19:54, 24 June 2016 (UTC)

The juxtaposition of words "universal trinity" appears in that source, but it does not correspond to the article that you wrote. If you want to write an article based on secondary sources, then nothing is stopping you from doing that. That article may or may not be deleted, depending on whether it conforms to our policies and guidelines. Sławomir Biały (talk) 20:23, 24 June 2016 (UTC)

The universal trinity in that source is the principle of formation which is explained as the origin of every form (like calculation which is the origin of every calculation result) the principle of perception as intelligence (which is exactly that what someone needs to build proofs) and the principle of choice from beings (who of course have to make individual decisions involving circumstances that are not fully understood exactly like unsolved conjectures which are also not fully understood). These parallelisms of meaning are obvious here and they are common in theosophic discourse, but not in mathematics, so please restore the article in my namespace so that such theosophic parallelisms can be completed with proper sources. MathLine (talk) 17:11, 25 June 2016 (UTC)

Sounds like original research to me. As I said, if you want to write an article based on sources, no one is stopping you. That article may or may not be deleted based on whether it conforms to policies. But this latest post does not really convince me that you understand why your original article was deleted. If we are in for more of the same, then this is not really a constructive use of anyone's time. Sławomir Biały (talk) 17:29, 25 June 2016 (UTC)

You should look into Wikipedia:Requests for undeletion. Ozob (talk) 18:10, 25 June 2016 (UTC)

Looking for feedback on a tool on Visual Editor to add open license text from other sources

Hi all

I'm designing a tool for Visual Editor to make it easy for people to add open license text from other sources, there are a huge number of open license sources compatible with Wikipedia including around 9000 journals. I can see a very large opportunity to easily create a high volume of good quality articles quickly. I have done a small project with open license text from UNESCO as a proof of concept, any thoughts, feedback or endorsements (on the Meta page) would be greatly appreciated.

Thanks

--John Cummings (talk) 14:37, 28 June 2016 (UTC)

Characteristic equation

There are four articles that link to the WP:DAB page characteristic equation, and I suspect that only this project's participants will be able to correctly disambiguate them. The four articles are:

• Angle condition
• Canonical analysis
• Closed-loop pole
• Magnitude condition

Disambiguation has been needed for two and a half years. Would anyone here like to tackle these? We at WP:DPL would be most grateful. — Gorthian (talk) 17:31, 27 June 2016 (UTC)

These four articles have been created by the same user. All have multiple issues (even is the template {{multiple issues}} has not been added to all). Clearly, "characteristic equation" does not refer to any of the meanings listed in Characteristic equation, and the disambiguation cannot been done without cleaning up the whole articles. D.Lazard (talk) 18:10, 27 June 2016 (UTC)

Ah. I wondered why they'd languished so long. If you agree, I think I'll just unlink that term in each one.

On a somewhat separate issue, is the dab page okay as it is? Besides matters of style, I mean: the definitions, completeness, etc. Or is it really a broader topic instead of several specific definitions? — Gorthian (talk) 22:08, 27 June 2016 (UTC) (Pinging @D.Lazard:, as I should have done in my reply. — Gorthian (talk) 00:17, 28 June 2016 (UTC)

To editor Gorthian: I have expanded Characteristic equation. There are probably other uses of "characteristic" and "characteristic equation" in mathematics, but I have not them in mind. This cannot be the subject of a broad-concept article, as "characteristic" is generally used in mathematics to denote a tool (usually simpler) used to solve a problem or classify its solutions. There are thus no relation between the various technical meanings of the word. By the way, after having read Control theory, it seems that, in this four articles, "characteristic equation" refers to the equation associated to the characteristic polynomial of a matrix. However, the articles are very confusing, and disambiguating the link is of no help for understanding the articles. D.Lazard (talk) 09:13, 28 June 2016 (UTC)

To editor D.Lazard: Thank you for adding characteristic polynomial. I am going to simply unlink the term in those four articles; whoever decides to untangle them can deal with linking at that time. Thank you for your help! — Gorthian (talk) 18:31, 28 June 2016 (UTC)

Continuum expression of the first law of thermodynamics

I'm having a disagreement with an editor over the new article continuum expression of the first law of thermodynamics. This seems like a reasonable equation to have covered somewhere on Wikipedia. I've checked the citation. An editor with apparently no knowledge of the subject, and also apparently someone unable to give a clear reason, is insistently replacing this new article with a redirect to first law of thermodynamics, where the expression in continuum mechanics is not given. I'm hardly an expert on continuum mechanics, but this does seem like something worth having an article on, and a stub seems like a good start. Sławomir Biały (talk) 00:43, 30 June 2016 (UTC)

It is now at AfD. Sławomir Biały (talk) 01:00, 30 June 2016 (UTC)

Jul 2016

Requested move

There is a requested move going on at Talk:Root-finding algorithm#Requested move 22 June 2016 that may be of interest to members of this project. Jenks24 (talk) 04:27, 1 July 2016 (UTC)

New mathematics-related AfD

Please see Wikipedia:Articles for deletion/Linear number. —David Eppstein (talk) 18:52, 2 July 2016 (UTC)

Multiple failures to parse

In the article titled First law of thermodynamics (fluid mechanics), one finds these words near the beginning:

In fluid mechanics, the first law of thermodynamics takes the following form:

Just below that, I find this:

Failed to parse (syntax error): \frac{D E_t}{D t}=\frac{D W}{D t} + \frac{D Q}{D t} \to \frac{D E_t}{D t} = \nabla\cdot({\bf \sigma\cdot v}) - \nabla\cdot{\bf q}

Then the word "where:" followed by this:

• Failed to parse (syntax error): \bf\sigma is the Cauchy stress tensor.
• Failed to parse (syntax error): \bf v is the flow velocity.
• and Failed to parse (syntax error): \bf q is the heat flux vector.

All but two of the instances of displayed TeX in the article just say "Failed to parse", followed by the TeX code.

But when I log out, the are rendered normally.

What's going on and how can the problem be fixed? Michael Hardy (talk) 20:33, 3 July 2016 (UTC)

• Special:Preferences → Appearance → Math → Select "MathML". Does this fix it? --The1337gamer (talk) 20:42, 3 July 2016 (UTC)

I removed the "\bf" tag in the math text ([20]). I think this is what was causing the parse errors. --The1337gamer (talk) 20:48, 3 July 2016 (UTC)

Replacing "\bf" by "\mathbf{..}" will also fix the parsing problem, but this changes the font as well as bolding the term. --Bill Cherowitzo (talk) 21:00, 3 July 2016 (UTC)

I've implemented that solution for now. But, this appears to be a bug in the LaTeX processor. In my opinion, that's not something to be "fixed" by removing \bf from mathematics articles, but something to be fixed by the developers. Given the recent vast overall improvements to the mathematical rendering, it's quite natural for there to be a few bugs that need to be worked out. Sławomir Biały (talk) 21:07, 3 July 2016 (UTC)

Sergei Nikolaevich Chernikov

A new biographical article about a Russian mathematician noted for his work on group theory and linear inequalities. The article could use some help fleshing out some detail of his contributions to the subject. Roger (Dodger67) (talk) 11:52, 7 July 2016 (UTC)

There is a picture in German Wikipedia. Maybe you could try to import that picture to here (or Wikimedia commons). YohanN7 (talk) 12:05, 7 July 2016 (UTC)

It's already in Commons so I added it to the infobox. Roger (Dodger67) (talk) 15:51, 7 July 2016 (UTC)

So far we've done some formatting and "cosmetic" edits but the original author requested assistance at AFC with expanding the information about his work and notable contributions to mathematics. Roger (Dodger67) (talk) 15:56, 7 July 2016 (UTC)

How to code Σ¹₁

the analogous problem is Σ¹₁-complete.

One could set this as <math> \Sigma_1^1 </math> and along with it tolerate the resulting mismatches in font sizes and the fact that the appearance of $\Sigma _{1}^{1}$ varies with user-preference settings and browsers, but if I want to go with the first notation above, is there a way to get better vertical alignment of the subscript and the superscript? Michael Hardy (talk) 20:59, 9 July 2016 (UTC)

Does this work? Σ¹
₁ --JBL (talk) 21:07, 9 July 2016 (UTC)

Oh, very nice! I did not know about that. --Trovatore (talk) 21:16, 9 July 2016 (UTC)

Yes. I learned of it recently from some of Tomruen's edits. --JBL (talk) 21:25, 9 July 2016 (UTC)

Also see {{su}}. Sławomir Biały (talk) 22:36, 9 July 2016 (UTC)

Tau (constant)

Please see Tau (constant), a new article that looks a bit iffy. Anna Frodesiak (talk) 04:02, 10 July 2016 (UTC)

There has already been at least one AfD on this. My impression is that the tau enthusiasts are very persistent but without much grasp of Wikipedia policy. Anyway, I redirected it to the same target as Tau (mathematical constant). —David Eppstein (talk) 04:15, 10 July 2016 (UTC)

I think they should have defined $\pi \equiv 2\pi$ , becuase to me Tau just looks nasty for $2\pi$ , like a legless $\pi$ . No offence.

But if the Tau reform will be accepted, I be happy to use it. יהודה שמחה ולדמן (talk) 08:52, 10 July 2016 (UTC)

An observation: τ only appears to become important enough for an encyclopedia around mid-Summer (and more specifically close to the date June 28). This suggests that the "movement" for the promotion of τ really amounts to a promotion of τ day more than anything else, with a complicit media desperate to fill the 24 hour news cycle with answers to the question "Why is today significant?", regardless of how far-fetched and unfounded the answers might actually be. While it is possible that one day there will be enough for a separate article on the constant, at the moment I still do not see significant coverage in reliable sources that would allow us to say more than we already do in the paragraph dedicated to the constant in the popular culture section of the article pi. Sławomir Biały (talk) 12:15, 10 July 2016 (UTC)

Inline Tex

Since MathML has become default and some bugs have been fixed, most of my resistance towards using Tex inline is gone. (PNG displayed inline Tex looked a^W_ful inline.) What are the general feelings about recommending Tex for all math from now on? Does inline MathML display well on most (all?) devices? YohanN7 (talk) 12:23, 11 July 2016 (UTC)

It still doesn't match the text in font, baseline, or size for me (on a Mac using Chrome), despite its recent improvements. So it remains worse-looking than {{math}} for formulas that can be formatted using {{math}}. —David Eppstein (talk) 16:16, 11 July 2016 (UTC)

However, I think the rationale for replacing inline TeX with {{math}} has gotten a lot weaker. (Not that there was ever much consensus for this, under MOS:RETAIN, but it was largely considered acceptable wikignoming until now because inline TeX was simply so awful until now.)

Also, I think we have passed a tipping point in which we should recommend that inline TeX for formulas using special symbols like "⟨" and "⟩" that aren't rendered properly on some browsers. (E.g., the article Hilbert space uses these.) Sławomir Biały (talk) 16:24, 11 July 2016 (UTC)

Except where there were RETAIN issues or already established conventions, I use TeX for all math markup, to keep displayed and inline math typography consistent with each other. Hence I'd support recommending TeX for all math markup for new articles and where doing so doesn't go against already established practice in current articles. --Mark viking (talk) 17:35, 11 July 2016 (UTC)

Parabolic partial differential equation

Does the article Parabolic partial differential equation look like it is complete? If not could someone make some notes on its talk page about what it needs? (Thre is actually a comment there about it needing something but doesn't say what and is from 2007.) Thank you. RJFJR (talk) 01:46, 13 July 2016 (UTC)

Article Möbius energy

There seems to be an important thing missing in this mathematics article. I invite to please see Talk:Möbius energy. Mr. Barris (talk) 17:34, 15 July 2016 (UTC)

I just provided there a link to articles with the definition. Boris Tsirelson (talk) 19:19, 15 July 2016 (UTC)

New method to traverse binary trees?

Did I encounter a new way to traverse binary trees or is this method mentioned on some existing page? Jidanni (talk) 15:54, 15 July 2016 (UTC)

This page is primarily intended for discussion of the creation and maintenance of Wikipedia's mathematics articles. You could ask about this at Wikipedia:Reference desk/Mathematics. Michael Hardy (talk) 14:14, 16 July 2016 (UTC)

Article: Ellipse

Could do with an additional pair of eyes the recent edits to Ellipse. See also my talk page for a discussion on it.--JohnBlackburne^words_deeds 14:31, 16 July 2016 (UTC)

PseudoScientist seems to know his stuff. Apparently, this is his area of expertise. What sense does it make to object to a word "amazing" that did not appear in the article? His chosen word "concise" seems appropriate for describing such formula. Besides, I see his point that the formula is "surprising" as it did not appeared before 2011. He is being totally honest with fully crediting its author.2A00:1370:8128:73E:C811:B591:263B:B6C6 (talk) 15:40, 16 July 2016 (UTC)

There is a related problem with Derivation of the Cartesian form for an ellipse which is lacking any sources. --Salix alba (talk): 20:05, 16 July 2016 (UTC)

I have sent that article to AfD. Please comment there. GeoffreyT2000 (talk) 20:56, 16 July 2016 (UTC)

Strange edits from IP

60.231.179.112 (talk · contribs · deleted contribs · logs · filter log · block user · block log) is (helpfully) tagging dead links in math articles. In the process of doing that, however, they are also (less helpfully) replacing links to sections of articles with links to redirects. For example, this edit replaces a perfectly reasonable piped link with a link to a cryptic redirect. This edit replaces unambiguous links with redirects like coordinate chart that at least have the potential for ambiguity. WP:NOTBROKEN seems to urge against going the other way, replacing redirects with direct links. I would think that this would cut both ways. Anyway, I have reverted a few of the more questionable edits, but more eyes might be warranted. Sławomir Biały (talk) 11:56, 17 July 2016 (UTC)

There are times that redirects are preferred to section links -- when there should be such an article, and when the section isn't quite right. But this is something which should be done by a human because it needs to distinguish that special case from others which make the links more cryptic. - CRGreathouse (t | c) 21:39, 17 July 2016 (UTC)

Yes, for example this edit replaced a link to characteristic equation (specifically with that title) to secular equation (an apparently rarely used synonym) and a general link to criteria for root multiplicities to something called Scree's test, which redirects to the same section, even though in the context it is not specifically Scree's test that is relevant. Sławomir Biały (talk) 21:43, 17 July 2016 (UTC)

Should the "Dirac delta function" be referred to as an "idiom"?

I have reverted this edit to Dirac delta function. There is an editor who insists on it at Talk:Dirac delta function/Archive 1#Can we rename it to 'Dirac delta distribution' ?. Please comment there. Sławomir Biały (talk) 11:31, 18 July 2016 (UTC)

Category:Science technology engineering and mathematics has been nominated for discussion

Category:Science technology engineering and mathematics, has been nominated for possible deletion, merging, or renaming. A discussion is taking place to see if it abides with the categorization guidelines. If you would like to participate in the discussion, you are invited to add your comments at the category's entry on the categories for discussion page. Ottawahitech (talk) 09:38, 19 July 2016 (UTC)please ping me

Request for un-doing an old merge

I'd like to undo a merge that was done some time ago of the page Teichmüller modular group into the page mapping class group. The former is a special case of the latter but it is of enough interest to deserve its own page (in fact, in geometric group theory the name "mapping class group" is reserved by default to that of a surface). An informative analogy is to compare the situation to the similar one between braid groups and Artin groups.

One of the reasons advanced for the merger was that "In fact, Teichmueller modular group is not heard among experts as mapping class group", which is a bit dubious (typing this term in Google yields enough results, and this is definitely a terminology I've heard people in the subject use, though not as frequently as "mapping class group"), but a better name for the page might be "Mapping class group of a surface".

I'm mostly asking this because I've been revising the page on Teichmüller space and created a page on the curve complex and both topics are heavily related to the mapping class group, so I'd like to have a decent page on the latter. jraimbau (talk) 10:02, 8 July 2016 (UTC)

Since nobody objected I have written a new page, Mapping class group of a surface. It has some overlap with Mapping class group (inevitable and not a problem in my opinion). I also changed some redirects from pages that linked to the later; one remaining is Torelli group for which the content is similar on both (perhaps a bit clearer on the older page); since this topic deserves in my opinion to have its own page someday I am fine with that for the moment. jraimbau (talk) 17:07, 19 July 2016 (UTC)

Edit proposal for (complex) antiderivative

A proposal appeared:

Talk:Antiderivative (complex analysis)#Edit proposal

Hope this is a right place for the message. If it isn't, feel free to move this info elsewhere. --CiaPan (talk) 20:53, 19 July 2016 (UTC)

Content (measure theory)

The feedback request services just notified me about a RFC at Talk:Content (measure theory) about how it relates to a pre-measure. I know nothing on the subject, so I hope someone more knowledgable than me could respond. --Salix alba (talk): 06:37, 20 July 2016 (UTC)

Fresnel integral

Last night I wrote out the derivation of $\int _{0}^{\infty }\sin(x^{2})dx$ and $\int _{0}^{\infty }\cos(x^{2})dx$. The formatting of the notation (in particular the spacing) doesn't look the prettiest and I may have missed a few details, so I'd like someone else to take a look as well.--Jasper Deng (talk) 02:59, 21 July 2016 (UTC)

Do you mean these two lines?

$\int _{0}^{\infty }e^{-ir^{2}}{\frac {\sqrt {2}}{2}}(1+i)\mathrm {d} r$.

$\int _{0}^{\infty }(\cos(r^{2})-i\sin(r^{2})){\frac {\sqrt {2}}{2}}(1+i)\mathrm {d} r={\frac {\sqrt {2}}{2}}\int _{0}^{\infty }[\cos(r^{2})+\sin(r^{2})]+[\cos(r^{2})-\sin(r^{2})]i\mathrm {d} r={\frac {\sqrt {\pi }}{2}}+0i$

You may try inserting a 'narrow space' \,, for example:

$\int _{0}^{\infty }e^{-ir^{2}}\,{\frac {\sqrt {2}}{2}}\,(1+i)\,\mathrm {d} r$.

$\int _{0}^{\infty }(\cos(r^{2})-i\sin(r^{2}))\,{\frac {\sqrt {2}}{2}}(1+i)\,\mathrm {d} r={\frac {\sqrt {2}}{2}}\int _{0}^{\infty }[\cos(r^{2})+\sin(r^{2})]+[\cos(r^{2})-\sin(r^{2})]\,i\,\mathrm {d} r={\frac {\sqrt {\pi }}{2}}+0i$

Additionally you may want to replace outer parens with they \big versions:

$\int _{0}^{\infty }e^{-ir^{2}}\,{\frac {\sqrt {2}}{2}}\,(1+i)\,\mathrm {d} r$.

$\int _{0}^{\infty }{\big (}\cos(r^{2})-i\sin(r^{2}){\big )}\,{\frac {\sqrt {2}}{2}}(1+i)\,\mathrm {d} r={\frac {\sqrt {2}}{2}}\int _{0}^{\infty }{\big [}\cos(r^{2})+\sin(r^{2}){\big ]}+{\big [}\cos(r^{2})-\sin(r^{2}){\big ]}\,i\,\mathrm {d} r={\frac {\sqrt {\pi }}{2}}+0i$

If the over-sized fraction is what concerns you, replace it with 'tiny frac' \tfrac:

$\int _{0}^{\infty }e^{-ir^{2}}\,{\tfrac {\sqrt {2}}{2}}\,(1+i)\,\mathrm {d} r$.

$\int _{0}^{\infty }{\big (}\cos(r^{2})-i\sin(r^{2}){\big )}\,{\tfrac {\sqrt {2}}{2}}(1+i)\,\mathrm {d} r={\tfrac {\sqrt {2}}{2}}\int _{0}^{\infty }{\big [}\cos(r^{2})+\sin(r^{2}){\big ]}+{\big [}\cos(r^{2})-\sin(r^{2}){\big ]}\,i\,\mathrm {d} r={\tfrac {\sqrt {\pi }}{2}}+0i$

You might also want to browse Help:Displaying a formula for more options :) --CiaPan (talk) 06:44, 21 July 2016 (UTC)

@CiaPan: Thanks. It's more like my not liking how, in the longer line, the plus and minus signs have no spacing between them and the following terms, though that seems to be (on closer examination) an artifact of my using the deprecated LaTeX rendering rather than MathML. I was wondering if there was a wikiproject consensus on how I should style it, and whether there are any mathematical problems with what I wrote (I think it looks rigorous enough, though).--Jasper Deng (talk) 07:10, 21 July 2016 (UTC)

A Dedekind's theorem

The article Chinese remainder theorem has a section § Dedekind's theorem, which is about "Dedekind's Theorem on the Linear Independence of Characters". I do not know this theorem, and the section does not provide any source or link. Moreover, the given proof does not involve the Chinese remainder theorem, but its generalization to arbitrary rings, which, as far as I know, is generally not known under this name.

Thus this article is not the right place for this Dedekind's theorem. Should this section be simply deleted, or moved elsewhere (where?) D.Lazard (talk) 09:10, 22 July 2016 (UTC)

This theorem also called Dedekind's lemma and is a topic in Galois theory, e.g., Milne's field theory notes p.51, or [21]. I don't know a good target article for this material. It is used in the the normal basis theorem, so possibly Normal basis? --Mark viking (talk) 10:53, 22 July 2016 (UTC)

Set builder notation

The article Set builder notation has languished for some time in a strange state. Lately a couple users, including me, have been making efforts to improve it. Please feel free to come help bring it up to a nice state, and to make sure that the article has the right POV overall. Any references to undergraduate or graduate level books that define the notation in detail would be very welcome. — Carl (CBM · talk) 13:28, 25 July 2016 (UTC)

Pages on algebraic tori

I have recently read the page on the notion of maximal torus. This article deals only with tori in compact Lie groups. Though the case of compact Lie groups should be discussed in this context, I see no reason why the article should be restricted to it. In fact I see a few arguments in favor of the opposite stance :

• tori in noncompact semisimple groups are used heavily in the theory of symmetric spaces ;
• They are also important for the classification of semisimple Lie groups (which in general is more complicated than that of only compact groups, but follows similar lines);
• the distinction between groups having compact maximal tori (such as SL₂(R)) and those not having them (for example SL₃(R)) is important for their representation theory.

In addition, I think the article should be significantly rewritten to include tori in semisimple algebraic groups over arbitrary fields (which are quite important for the structure theory of these groups and also for the geometry associated to them).

To sum up, I think the Lie theory sections on Wikipedia would benefit from a reorganisation of the topics related to algebraic tori. In my opinion there should be three articles on the subject:

• Cartan subalgebra which exists and seems good enough;
• Torus (subgroup) which does not and should include the definition of tori in the setting of algebraic groups, the definition of the split rank of semisimple algebraic groups (in particular the real rank, currently a redirect to Iwasawa decomposition which in my opinion is not its proper place);
• Cartan subgroup which exists but might be rewritten a little, in particular including the contents of "maximal torus" (the notions are not identical but the minor differences between them should fit in a small paragraph in this article).

I'd be happy to do this re-organising myself (this might take some time) but since this would be a fairly big change for the articles in question, if anybody is interested in Lie theory and algebraic groups and likes the articles as they are I'd be happy to discuss with them other ways to incorporate what I think is needed. jraimbau (talk) 17:09, 19 July 2016 (UTC)

I agree we don't seem to have a significant discussion of a maximal torus in the context of the theory of linear algebraic groups (say, conjugacy or relation to Cartan subgroups). "Algebraic torus" is nicely written (and fairly complete) but is written from the point of view of group schemes (in fact the reference there is SGA). For example, a lot of materials (Galois stuff) become insignificant over an algebraically closed field. A simple solution is add more materials to algebraic torus, in a way of examples, say, on the group of real points. A section on "complex torus makes sense. A section on a torus action makes sense but that one would require a separate article. A significant solution is to start a separate article, but I'm not sure if that is needed (but that's just my opinion). -- Taku (talk) 21:57, 25 July 2016 (UTC)

Yes, I noticed this article since I posted this proposal and I am currently working on adding a first part dealing exclusively with tori over field and explaining quickly the links to the classification problem for algebraic groups, and to the geometry of buildings and symmetric spaces. It would be nice if someone would then rewrite the part with arbitrary base scheme to make it more readable. jraimbau (talk) 07:56, 26 July 2016 (UTC)

Sharkovskii / Sharkovsky

Our article about Sharkovskii's theorem spells Sharkovskii's name one way, but our article about Oleksandr Mykolaiovych Sharkovsky spells his name differently. I just fixed the first article so that it used only one spelling instead of two, and in the course of doing that I got very confused about which redirects where going where. It would be less confusing if we were able to adopt a single spelling throughout.

I tried to find out which spelling was preferred, but both spellings seem to be common. The original Ukrainian spelling is “Шарко́вський”. I am not sure how to proceed here. Probably doing nothing is acceptable, but I thought I would bring it up. —Mark Dominus (talk) 14:55, 25 July 2016 (UTC)

There is also disagreement about how to transliterate “Миколайович”: All of “Mikolaiovich”, “Mykolaiovich”, and “Mykolaiovych” appear. —Mark Dominus (talk) 14:56, 25 July 2016 (UTC)

Some people spell the name beginning with an ‘S’ instead of ‘Sh’, but I think this is clearly wrong. We should have redirects from these spellings, but should not use them in articles. —Mark Dominus (talk) 15:06, 25 July 2016 (UTC)

There is a standard way (actually more than one depending on year) for transliterating Ukrainian into the Latin alphabet, and then there is how S spells his own name. Since the web page listed in our article as his home page uses the "Sharkovsky" spelling, that is what I would prefer in the article about him. As for the theorem, my impression from Google scholar is that both spellings are roughly equally prevalent, but that "Sharkovskii's theorem" is a more old-fashioned spelling and that new publications are breaking roughly 2-to-1 for "Sharkovsky's theorem". Whether that's enough to change the name is unclear to me but we should probably at least mention both spellings in the article. —David Eppstein (talk) 20:54, 25 July 2016 (UTC)

Awesome, I hadn't noticed the link to Sharkovsky's home page. That gives me a clear way forward. I will of course leave redirects in place for all alternative spellings. —Mark Dominus (talk) 14:40, 26 July 2016 (UTC)

For the record, the spelling given there (http://imath.kiev.ua/~asharkov/) is “Oleksandr Mykolayovych Sharkovsky”. —Mark Dominus (talk) 15:11, 26 July 2016 (UTC)

Also for the record, there is a note on the talk page, ostensibly from Sharkovsky’s son, stating that “The proper latinization of "Миколайович" is Mykolaiovych”, which conflicts with the spelling on Sharkovsky’s web page. I didn't see this until after I renamed the page. —Mark Dominus (talk) 15:29, 26 July 2016 (UTC)

Proposed deletion of Musean hypernumber

The article Musean hypernumber has been proposed for deletion because of the following concern:

Multiple concerns: *The content in itself seems not notable at all; in fact the sources point to either Charles Musès (who wasnt a mathematician, but, as wiki itself says, "an esoteric philosopher") or to Jens Köplinger, who seems the author of this article itself, as he says in the talk at special:diff/99213211: "In order to support notability, you were asking whether these numbers were "widely studied"? I wish they were. To me they are a widely referred-to concept that is in deep need of study. Other than Charles Musès and Kevin Carmody, I only know about myself [22] having formally published in a mathematical context. Informally but mathematical, there are references in monographs by Robert de Marrais (e.g. [23] and others) or self-maintained web pages (e.g. Tony Smith's [24]). But, most other references are outside the field of mathematics, in attempts to link consciousness with mathematical concepts, and in spiritual and religous ideas (an internet search shows all kinds of mentions, some serious; I don't want to go there).". *References to mathematics and physics terminology is all wrong and nonsensical, how is that an algebra? How such construct relates to quantum consciousness, as Musean hypernumber#Visions_of_applicability implies? It seems non-rigourous patent nonsense. *Even if this were notable, its lack of mathematical rigor and standard terminology, as well as its original creator being an "esoteric philosopher", would make the perspective from which is told this article completely wrong. If this isnt real mathematics, but rather "the view of mathematics said philosopher had" the article must state it and not trying to sell such concept as if it had the same mathematical status of real analysis.

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the {{proposed deletion/dated}} notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the article to address the issues raised. Removing {{proposed deletion/dated}} will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Nickanc (talk) 13:45, 26 July 2016 (UTC)

due to a revert, it is now an AfD.--Nickanc (talk) 12:31, 27 July 2016 (UTC)

Content (measure theory) (please revert me?)

User:174.3.155.181 vastly expanded Content (measure theory). User:Kusma reverted that edit citing where it was incorrect. User:Mark viking seemed to further explain the problems with 174.3.155.181's edit in talk. A week later 174.3.155.181's sock-puppet account reverted it all back again. I have reverted that last edit since it wasn't kosher re: fabricating support for an edit via sock-puppetry and putting on a charade of being someone else. I have no idea if its a valid good-faith edit mathematically speaking, somebody in this project should probably look it all over. Fountains of Bryn Mawr (talk) 14:49, 27 July 2016 (UTC)

In the meantime the IP has been blocked for 3 months and Gagz7 has been indefinitely blocked for socking. —David Eppstein (talk) 16:08, 27 July 2016 (UTC)

A Categories for deletion discussion WikiProject members may be interested in.

It concerns the categorizing of Mathematicians by city. The discussion can be found here[25]....William, is the complaint department really on the roof? 21:08, 27 July 2016 (UTC)

Notable?

I thought that maybe the articles Tacito Augusto Farias and Douglas Smigly should be deleted for lack of notability. The second one is just 18 years old undergraduate student and the user who created it here also seems to be doing cross-wiki mass creation... TunksunT (talk) 23:43, 27 July 2016 (UTC)

XfD discussion

There is a discussion on whether to delete Draft:Basic theorems of algebraic K-theory at Wikipedia:Miscellany for deletion/Draft:Basic theorems of algebraic K-theory. Ozob (talk) 01:00, 28 July 2016 (UTC)

Rassias' conjecture

An article Rassias' conjecture was created some time ago, possibly by Rassias himself, as something of a promotional piece. It has been carefully sourced and I feel that is does meet WP:GNG and so I have been editing it recently to improve its quality. Some fresh eyes would probably help improve the article further.

CRGreathouse (t | c) 04:03, 29 July 2016 (UTC)

Almost integer

In the example at the top of the almost integer article, there is a formula which appears truncated to me. <math>\frac{1}{2}\sqrt{\frac{1}{30}(61421-23\sqrt{5831385})} </math> appears to me with the integer 58313 instead of 5831385 under the square root - in other words, the expression is truncated. Any idea why this is or how to fix it? The illustration of the golden rectangle near the top of the golden ratio article also has a truncated formula. EdChem (talk) 10:13, 29 July 2016 (UTC)

I see the whole integer (in the image thumb), and also no issue in golden ratio. What browser/OS are you using and what is your math preference set to? --Izno (talk) 11:41, 29 July 2016 (UTC)

I'm using Edge in Win 10. If I open in IE 11, the full formulae show. No idea where math preferences set up is. Thanks. EdChem (talk) 12:18, 29 July 2016 (UTC)

Draft:Quasi-abelian category

Anyone want to take a crack as to whether this Draft should be moved to mainspace?Naraht (talk) 18:06, 29 July 2016 (UTC)

The topic looks notable; a search produces multiple RS. This looks like a solid start-class article, with the basics of the definition, examples, and good references. --Mark viking (talk) 18:15, 29 July 2016 (UTC)

I have now accepted this AfC draft and moved it to mainspace. GeoffreyT2000 (talk) 18:22, 29 July 2016 (UTC)

Aug 2016

Math DAB links

There are four articles linking to the DAB page Pushforward (or to redirects to it); those links need to be disambiguated. Several of us at WP:DPL are scratching our heads over what to do with them. If anyone here is willing to tackle them, we'd be most grateful.

The articles are:

• Contraction principle (large deviations theory)
• Hodge bundle
• Rate function
• Composition operator

Many thanks for your attention! — Gorthian (talk) 07:17, 4 August 2016 (UTC)

It seems that in the Hodge bundle article "pushforward" refers to Direct image of a sheaf and in all others to Pushforward measure. I changed the links accordingly. jraimbau (talk) 08:24, 4 August 2016 (UTC)

Thank you for such quick action! — Gorthian (talk) 09:11, 4 August 2016 (UTC)

Slowly varying function

Under "Karamata's characterization theorem", β need not be non negative, see Theorem 1.4.1 of Bingham, Goldie, Teugels. Accordingly, ρ can also be negative. — Preceding unsigned comment added by 62.141.176.1 (talk) 11:23, 4 August 2016‎

Not knowing about that theorem, I won't attempt to correct any problems with the article. But I wonder why you don't. Michael Hardy (talk) 04:03, 6 August 2016 (UTC)

Measurable and μ-measurable functions

I posted a question in over at the measurable function talk page some time ago. Is there any sense to it? YohanN7 (talk) 11:46, 10 August 2016 (UTC)

Torsion coefficient (topology)

Article needs attention from an expert in algebraic topology. I posted a set of questions and objections on its talk page: Talk:Torsion coefficient (topology) 67.198.37.16 (talk) 20:16, 10 August 2016 (UTC)

Programmatic examples

Coming from a programming background, and not having much formal math schooling since high school, I find it difficult to translate the abstract mathematical notation into a language I can actually programmatically calculate. I would hazard a guess that I am not alone in this regard, although this is a bit anecdotal. Therefore, it would be awesome if a Wikiproject was started that had programmatic examples, in addition to the more abstract ones written in mathematical notation. It might even be possible to have this translation be automatic (sympy.org?). I think it would be much easier to learn complex mathematics if it was taught using python rather than Greek. --Aaron E-J (talk) 18:02, 6 August 2016 (UTC)

Can you be more specific? Which article(s) do you have in mind? Many mathematical topics cannot be programmed. For many topics that can be programmed, programming them is a difficult task, which can still be an active subject of research (a typical example is integer factorization), and the programs may be so complicate that they can be read only by specialists. On the other hand, many math. articles provide pseudo-code, which is the standard method for describing programming methods in a way which is independent of a specific programming language. Nevertheless, I agree that too many articles contain complicate descriptions of algorithms, which would be much easier to understand, by simply providing pseudo-code. Also, too many articles can be understood only by people that already know the subject. This is not because of the lack of programming examples, but, simply because they are badly written. Please improve them if you can. D.Lazard (talk) 20:13, 6 August 2016 (UTC)

I agree with D.Lazard. Many mathematical theorems use non-constructive existence proofs. The "non-constructive" part means that no algorithm is offered. I'm sure that there is a place for concrete algorithms in specific articles, but to ask Wikipedia to include an algorithm for converting mathematical proofs to algorithms is far too ambitious. Mgnbar (talk) 00:55, 7 August 2016 (UTC)

I guess what I am suggesting is programmatic examples of how you would utilize the theories, not complete proofs. Computer programs, when it comes down to it, are math. Obviously you cannot prove everything with only 1 and 0, but then an encyclopedia article is not a theorem, but an explanation of a theorem. --Aaron E-J (talk) 02:20, 7 August 2016 (UTC)

Some theories are easy to illustrate with programs, while others are not. There are topics that are well-understood from certain theoretical viewpoints but whose implementation is very subtle. For example, mathematical optimization of, say, a smooth real-valued function of several real variables is easy in theory: Find where the derivative of the objective function vanishes, compute the values of the function at those points, and also compute the function values along whatever boundary the problem might have. In practice this is so difficult that people devote their lives to it.

Whether or not providing pseudocode is feasible depends on the article. I'm sure there are articles that would benefit from pseudocode, or maybe even more than pseudocode. If you have some particular articles in mind, there are experts here who could take a look. Ozob (talk) 02:37, 7 August 2016 (UTC)

Perhaps this might help -- there are multiple books on category theory, with all the concepts illustrated in ML (programming language) or CaML. Since category theory undergirds the syntactic content of mathematics (e.g in the guise of topoi) then perhaps that could be an aid to understanding. As to actually putting program snippets into WP math articles -- thats a terrible idea -- its basically original research, unless you do it a la the aforementioned books. (The ML/CAML books are interesting precisely because ML adds types to lambda calculus, which then gives a nice bridge from category theory to type theory which is a HoTT topic these days). 67.198.37.16 (talk) 20:25, 10 August 2016 (UTC)

Mivar-based approach

This article, which is being translated from ru:Миварный подход, may be of interest. JohnCD (talk) 09:41, 11 August 2016 (UTC)

Mean value problem

Mean value problem is an article about a problem posed by Stephen Smale. I needs work. Michael Hardy (talk) 19:52, 12 August 2016 (UTC)

. . . and I've done a bit more work on it. But more is needed. Only one page links to it: the one on Smale's problems. Michael Hardy (talk) 01:59, 13 August 2016 (UTC)

Binary function

Binary function (i.e. a bivariate function, not a function with binary variables or values) has been proposed for deletion. It's been a problem article (e.g. no sources) for years, but maybe someone wants to take the effort to save it? —David Eppstein (talk) 06:35, 14 August 2016 (UTC)

Hi, I've done some work on it, but a lot of the sections are things I really don't know much about. Have removed the prod for now. Happy Squirrel (talk) 02:37, 17 August 2016 (UTC)

Convolution quotient

I've created a severely stubby new article title Convolution quotient. Clearly it needs work, but I'm done with it at least until morning. Michael Hardy (talk) 05:29, 19 August 2016 (UTC)

Josip Pečarić

• Josip Pečarić (edit | talk | history | protect | delete | links | watch | logs | views)

Two tags have been added to the article, apparently based on the description "a great name in the theory of inequality" based on this source. Is the source sufficient for the claim? Is it a reasonable statement? Please offer opinions at the article. Johnuniq (talk) 00:57, 20 August 2016 (UTC)

MoS indentation

Hi, I started a conversation regarding proper indentation of LaTeX formulas at Wikipedia talk:Manual of Style/Mathematics#Indentation which could use more voices to reach a consensus. Opencooper (talk) 12:29, 20 August 2016 (UTC)

Cyclic function up for deletion

The article Cyclic function has been proposed for deletion.  --Lambiam 22:25, 20 August 2016 (UTC)

Zermelo's navigation problem

Editor did 1/2 the math equations correctly, the rest show up garbled in the text. I haven't a clue what's going on. The creating editor is rarely on Wikipedia. Could somebody figure it out. Bgwhite (talk) 05:40, 20 August 2016 (UTC)

Now equations are not garbled. Boris Tsirelson (talk) 08:06, 20 August 2016 (UTC)

Thank you Boris Tsirelson. Boy, the page looks completely different with the equations displayed properly. Bgwhite (talk) 06:40, 22 August 2016 (UTC)

Dixon's elliptic functions

I have created a new article titled Dixon's elliptic functions.

The phrase "have regular hexagons as repeating units" may not be the most felicitous, but it's what I've got so far.

It is an amusing and slightly edifying exercise that takes a few seconds to show that "having hexagons as repeating units" in no way conflicts with the fact that the fundamental domains that repeat can be taken to be parallelograms. Michael Hardy (talk) 18:53, 23 August 2016 (UTC)

Mathematical model of flow processes

A new article titled Mathematical model of flow processes is incredibly messy. Whoever feels like cleaning up a mess should consider this one. Michael Hardy (talk) 13:01, 25 August 2016 (UTC)

I suspect we already have these documented at e.g. fluid dynamics and possible subsidiary articles. Should probably redirect there. --Izno (talk) 13:13, 25 August 2016 (UTC)

Infobox for operators

I was thinking it would be good to have infoboxes for operators such as the addition, division, dot product, cross product, &c. These infoboxes would have information on commutativity, associativity, &c. What do you think?

Sorry if this is the wrong place for this question. George Makepeace (talk) 14:17, 10 August 2016 (UTC)

I think you might mean operations, not operators. Gandalf61 (talk) 15:41, 10 August 2016 (UTC)

They do, but it isn't the most unambiguous language: operations are frequently called operators, especially in the context of programming. Terminology aside, I think an infobox is a pretty good idea — could contain properties of the operation itself (commutativity, associativity, arity, as well as some details on the normal representation/text encoding (unicode, ascii (and alternatives if applicable like ^ for exponentiation)). —  crh ₂₃  (Talk) 18:30, 10 August 2016 (UTC)

I think it's a great idea. Once you get the basic structure done, though, post a link here and give it 2–4 weeks for people to comment/improve before adding it to articles, since it will be used mostly on high-importance heavy-traffic pages. SamuelRiv (talk) 13:31, 25 August 2016 (UTC)

Math symbol code

Hi. I wonder how come the Greek alphabet letters are not independently coded like the regular coding of Anglo-Latino alphabet? Why write <math>\alpha</math> and not <math>α</math>? These letters are used so much.

And the same with symbols like ∅ instead of {\empty,\emptyset,\varnothing}, ℕ instead of \N and so on.

In any way there is no consistency in many codings, like \N is $\mathbb {N}$ but \A isn't $\mathbb {A}$ but rather undefined.

Can someone change all this? יהודה שמחה ולדמן (talk) 15:05, 17 August 2016 (UTC)

As long as we use (a version of) TeX, this is not immediately possible. Probably, a preprocessor could help. Anyway, programmers of Wikimedia are needed for such job. Boris Tsirelson (talk) 16:06, 17 August 2016 (UTC)

But could\will this be changed? Why wasn't the Greek alphabet coded like this in the first place?

I think every single symbol should be coded. That way we will not need long code words, <math>≤</math> instead of <math>\ge</math> . The clumsiness will me moved to the software, which is anyway clumsy.

Why do we refer to these symbols just as 'characters' but not letters? יהודה שמחה ולדמן (talk) 16:48, 17 August 2016 (UTC)

Why? Because TeX was written at a time long before Unicode was invented, when we still used more limited character sets. (I would say ASCII, but I seem to remember that SAIL used its own idiosyncratic character set.) —David Eppstein (talk) 17:35, 17 August 2016 (UTC)

In the English alphabet there are 26 letters, in upper- and lower-case versions. We use many other symbols, such as digits and punctuation, that are not letters. We use the term "character" to encompass all of these symbols, including the letters. Is that what you were asking? Mgnbar (talk) 18:18, 17 August 2016 (UTC)

I was asking what is the real differene between the letter <math>a</math> to the greek letter <math>α</math> , and from here I'm asking about <math>≤</math> .

Did the computers decide which to accept? No. The people inventing computers did - by what we call 'programming'. The people. Is it that hard to get? יהודה שמחה ולדמן (talk) 18:28, 17 August 2016 (UTC)

Yes, and the people (mathematicians, computer scientists, physicists) settled on TeX as the lingua franca for mathematical typesetting 30 years ago. In academic publishing, it remains the dominant way to write math to this day. Wikipedia allows for alternative encodings, but TeX is not going away any time soon. On WP, there have been many discussions of HTML vs Unicode vs TeX, and there is never a consensus to adopt any one system to the exclusion of others. I prefer everything to be in TeX, but that will never happen and I respect the consensus. If you want to learn more about the consensus and recommended style, check out MOS:MATH#Typesetting of mathematical formulae. --Mark viking (talk) 19:09, 17 August 2016 (UTC)

To reply to your original question, the TeX math alpha is considered to be an italicized version of a Greek alpha. With respect to a Unicode representation, is it better to italicize a unicode "greek small letter alpha", or use the direct unicode "mathematical italic small alpha"? See Alpha#Computer_encodings for what I am referring to. --Mark viking (talk) 19:28, 17 August 2016 (UTC)

Template:Math is usually recommended for individual symbols, variables, and short equations/expressions, instead of <math/>. I even recommend using it to enclose all numbers and operators for things like 1+2=3α, which is {{math|1+2{{=}}3''α''}}. The central advantage goes to your primary objection: the template is coded by us for us, so we can make changes and adjustments as needed, since the needs of Wikipedia and web formatting are rather different from what TeX was designed for.

TeX of course can be modified and expanded as is done all the time (WP's <math/> is based on LaTeX). There are already projects for unicode and web, e.g. XeTex and MathJax, but they haven't been combined yet. SamuelRiv (talk) 14:51, 25 August 2016 (UTC)

Just look...

...what is happening to the article "Measure (mathematics)" (note its recent history). Boris Tsirelson (talk) 10:37, 25 August 2016 (UTC)

Maybe you could just tell us what's happening. Someone is vandalizing/spamming the citations? Mgnbar (talk) 10:54, 25 August 2016 (UTC)

Well, 49.147.175.127 insists that "Radon measures have an alternative definition in terms of linear functionals on the locally convex space of continuous functions with compact support. This approach is taken by Bourbaki (2004) and a number of other sources." and tries to exterminate the other (topology-free) approach (and replace references accordingly). Boris Tsirelson (talk) 13:20, 25 August 2016 (UTC)

I haven't followed this particular discussion, but of course everybody knows that some people erroneously think that Bourbaki is God. Michael Hardy (talk) 04:05, 27 August 2016 (UTC)

In fact, I like Bourbaki (at least, in some aspects); and indeed, Radon measures are beautiful. But I have two objections. First, measure theory is invariant under (invertible) measurable transformations (which was also emphasized in clumsy words by the anon: "Let composition of measurable functions is measurable, making the measurable spaces and measurable functions a category."); but topology is invariant under homeomorphisms, – much less. Second, an infinite-dimensional Gaussian measure (maybe the most useful probability measure) is not a Radon measure (since in infinite dimension every continuous function with compact support is identically zero). Boris Tsirelson (talk) 05:07, 27 August 2016 (UTC)

Deletion discussion for Alexander Kuznetsov

Alexander Kuznetsov (mathematician) has been nominated for deletion. Please participate in the discussion at Wikipedia:Articles for deletion/Alexander Kuznetsov (mathematician). —David Eppstein (talk) 18:55, 28 August 2016 (UTC)

Template:Statistics

Someone is going around adding {{statistics}} to a bunch of articles in mathematics and statistics. The template is very large: when subst'ed, it takes up about 14kb, and is being added to articles with only a passing significance in statistics, like Lp space. Two questions: (1) is it really helpful to the reader to have the entire outline of statistics in a navigation template, even on somewhat peripheral articles? (2) Do navigation boxes this large and complex really have any legitimate use in article space, outside of (say) portals, outlines, lists, and similar kinds of organizational media? Sławomir
Biały 14:40, 23 August 2016 (UTC)

I'm not a big fan of these navigational boxes and this is a good example of why. I think there ought to be some criteria for when and where they should be used. Restricting them to certain types of articles makes sense to me. --Bill Cherowitzo (talk) 17:14, 23 August 2016 (UTC)

Rather than immediately stripping navboxes from pages, I posted a suggestion to break up the Statistics template at their talk page. SamuelRiv (talk) 16:37, 25 August 2016 (UTC)

Count me as a vote that the answer to Sławomir's question 2 is "no." At the very least, the template should be collapsed by default. --JBL (talk) 16:53, 25 August 2016 (UTC)

User:Slawekb raised several issues.

1. The template is being added to ["a bunch of"?] "articles with only a passing relevance to statistics", for example, "Lp space".

First, regarding "articles" (plural). Please name another example of a mathematical article with "only a passing relevance to statistics" to which the box was added? I know of none.

The article Lp space explains the relevance to statistics:

Statistics

In statistics, measures of central tendency and statistical dispersion, such as the mean, median, and standard deviation, are defined in terms of L^p metrics, and measures of central tendency can be characterized as solutions to variational problems.

Indeed, when I added the statistics template to Lp space, my edit summary explained the relevance: "A standard hypothesis in mathematical statistics posits that a random variable be in an Lp space)". (Obviously the linear-space properties are crucial to averaging.) Nobody has removed the template from Lp space, the 2nd step in the BRD sequence.

2. The template is big.

A discussion of re-engineering the template at the statistics project would be reasonable. A notice on the talk page of the template alerted almost nobody.

Inserting the "state=collapsed" argument makes the template appear in one-line.

162.250.169.162 (talk) 11:47, 28 August 2016 (UTC)

I'm astonished that you would think that just because an article mentions statistics means that it should carry a complete navigation box for all things statitical. What conceivable purpose does this serve? Whether it is one line or not, it does add considerably to the page-load time. This is also particularly a concern for dialup or mobile users. Sławomir Biały (talk) 12:40, 28 August 2016 (UTC)

Astonishment at things I did not write and do not thing is your prerogative. :) I shall delete the template, following the BRD sequence.

Would you please state the (plural) mathematical-articles unrelated to statistics to which I, as you wrote before, added the template or please withdraw that statement 162.250.169.162 (talk) 13:59, 28 August 2016 (UTC)

Latin square and Fourier analysis are two obvious ones. It's unclear to me that this template is really appropriate even in many statistics articles, like covariance, since these are not top-level articles. Arguably, detailed navigation templates like this only belong on top-level articles like statistics (if anywhere). Sławomir
Biały 15:26, 28 August 2016 (UTC)

Thanks for replying. You must have used "someone" for several persons. :)

Please remove infoboxes where they don't belong (and add them where they help). Latin square could use an experimental or combinatorial design infobox, if one exists. Latin squares do not appear on the statistics infobox.

162.250.169.162 (talk) 16:00, 28 August 2016 (UTC)

@Slawekb: To say that Latin squares are unrelated to statistics is to be ignorant of statistics. Latin squares are used in the design of experiments. And in fact, that is stated in the first sentence of the article. Fourier analysis is of course used in statistics because Fourier analysis is used in just about everything. Michael Hardy (talk) 19:52, 28 August 2016 (UTC)

Pardon me, but this is just an irrelevant straw-man argument. I did not say that Latin squares have nothing to do with statistics. I did, however, question whether they are a sufficiently top-level statistical article to warrant having a huge template that contains an outline of all statistics placed on it. Addition is also used in statistics. Are we to put {{statistics}} on the article addition? Fourier analysis is used everywhere, so does every mathematics navigation template we can imagine belong on the article Fourier analysis. I'd be interested in how you weigh in on these relevant questions, rather than irrelevant ones of your own invention. 21:13, 28 August 2016 (UTC)

It wasn't an argument at all, and I wasn't suggesting that those infoboxes should be there. I was just saying that it's not true that Latin squares are unrelated to statistics. You had said they were obviously unrelated. Michael Hardy (talk) 05:18, 29 August 2016 (UTC)

I did not say this, although I see that you could have come to that conclusion. Do you have anything relevant to say, or is this going to degenerate into a discussion of who said what? Sławomir Biały (talk) 10:16, 29 August 2016 (UTC)

One-line template: "State=collapsed"

Indeed, as the documentation explains, the template is easily collapsed to one line

as is the probability distributions infobox

which is more relevant for this project. 162.250.169.162 (talk) 11:47, 28 August 2016 (UTC) 11:54, 28 August 2016 (UTC)

Collapsing does not reduce the size of the file which is downloaded when reading the article. Thus the objection about the size of the template remains valid. D.Lazard (talk) 13:01, 28 August 2016 (UTC)

The size is a valid concern, while at least another stated concern was shown to be invalid.

Are you proposing a maximum-size guideline for infoboxes (for the mathematics project)? If so, the large probability-distribution infobox should be discussed along with the statistics infobox? 162.250.169.162 (talk) 13:59, 28 August 2016 (UTC)

I removed the statistics toolbox from Lp spaces, following BDR.162.250.169.162 (talk) 14:06, 28 August 2016 (UTC)

Negative-dimensional space

I tripped over negative-dimensional space and ideas like reduced homology and K-theory sprang to mind, when I realized that the entire article seems to be some sort of non-mathematical, pop-sci original-research effort to grapple with the contents of one specific paper on arxiv. (The other citation in the article is to an art project mounted by a mathematician, who does mention reduced homology.) The whole thing is dazed and confused, as a result. Should this WP article be expanded into some sort of pop-sci exploration of "negative dimension", like some fun blog post somewhere? Is a pop-sci review really encyclopedic? Turning it into a review of a single arxiv article seems wrong; its not really notable. I don't see how to rescue this article. Perhaps someone can prod for deletion? Or something? 67.198.37.16 (talk) 21:22, 28 August 2016 (UTC)

(p.s. I've recently started stumbling over articles of this kind: they're always pop-sci attempts, blog-like in structure and approach, written primarily by a single non-expert author, containing confusing, inaccurate, misleading information, or maybe containing no workable information at all. Not just in math. I find them kind-of irritating, but am not sure what to do, if anything at all. Is there some general policy about this? I'm not mean-spirited enough to just start proding and afd'ing things...) 67.198.37.16 (talk) 21:22, 28 August 2016 (UTC)

Just as an aside, the only useful and mathematically valid concept involving negative dimensions that I'm familiar with is that (particularly in the context of the face lattices of polyhedra) it is convenient to define the dimension of the empty set to be −1. But that's not enough to form the basis of an article, and probably too far removed from the topics the one you point to is wrestling with. —David Eppstein (talk) 21:43, 28 August 2016 (UTC)

I think the article seems pretty fishy. I'll add to Eppstein's observation that sometimes negative dimensional tensors are considered in connection with the theory of spin networks. Roger Penrose wrote a paper about them in 1971. It's not clear to me in what sense they describe spaces. Sławomir Biały (talk) 21:53, 28 August 2016 (UTC)

Negative dimensional spaces have been around for a while and have been considered using different approaches. Mandelbrot considered spaces of negative dimension 26 years ago in the context of multifractals, e.g, Negative fractal dimensions and multifractals. May's book on algebraic topology discusses K-theory and negative spectra, A Concise Course in Algebraic Topology, apge 231, which seems the approach used in this article. Cvitanovic and Kennedy considered spinors in negative dimensions, Spinors in Negative Dimensions. Spin glasses and random fields also have a notion of negative dimension, e.g., Parisi's 1979 Random Magnetic Fields, Supersymmetry, and Negative Dimensions. A little research shows no pop science required. --Mark viking (talk) 23:51, 28 August 2016 (UTC)

Yes, except that all of those concepts of negative dimension are more or less completely unrelated to one-another. Its a fair bit of original synthesis to put all of those things into a single article. Now, maybe its excusable in a "list of negative-dimensional concepts", or some kind of disambiguation page. But simply rattling off all the places where one has ever thought of negative dimension is .. well, its still original research. Its still pop-sci. No one is actively crossing over from one field into another based on the fact that the word "negative dimension" got used in the papers. 67.198.37.16 (talk) 21:08, 29 August 2016 (UTC)

I refuted your assertion that the K-theory approach to negative dimensions is only based on a single arxiv paper; May's discussion is a tertiary RS that suggests this may be a more widely discussed and possibly notable approach. I also showed that the concept of negative dimensions have been considered by different people over decades; the concept seems broader than just a K-theory extension. But I never claimed these should be put all into the same article; that is your synthesis, not mine. If there are reviews out there comparing and contrasting the various approaches to negative dimensions, we can write a general article comparing and contrasting the the various approaches. Otherwise, it would be better to write articles on the individual approaches according the the availability of reliable sources. We describe, not prescribe. --Mark viking (talk) 02:31, 30 August 2016 (UTC)

I think you misunderstood my comments. I was about to *add* K-theory to that article, when I realized that doing so would be "original synthesis". So I pulled back and posted here. That article, as currently written, *is* based on a single arxiv paper that has nothing at all to do with K-theory. So, rather than refuting, you seem to be "violently agreeing" with me ... as far as I can tell, there are *zero* "reviews out there comparing and contrasting the various approaches to negative dimensions", which is why I suggested prodding that article. 67.198.37.16 (talk) 23:26, 30 August 2016 (UTC)

Font Size Of All Math Formulas

All the mathematical formulas in the "Rodrigues Rotation Formula" article appear in very small type; I'm guessing 8 point type on my computer. The text appears normal as 10 or 12 point type. This is only a problem for some of the math articles in Wikipedia. This should be an easy fix.

68.100.252.138 (talk) 15:45, 30 August 2016 (UTC)Maurice Daniel68.100.252.138 (talk) 15:45, 30 August 2016 (UTC)

That article looks normal to me. Are you viewing it in an ordinary browser, or on a mobile device? Is it only the inline mathematics formulas that look small, or the ones that display on their own lines? Sławomir Biały (talk) 16:34, 30 August 2016 (UTC)

That article has normal size math symbols for me, too (Latest Chrome on a modern Mac). I don't see any unusual math markup. --Mark viking (talk) 18:58, 30 August 2016 (UTC)

The article consistently uses the math template for inline math and Tex for displayed math. It is the combination that has produced the best average visual result, and looks fine for me too."Should be an easy fix..." is undue optimism. It will surely take another fifteen years to get right, and it is not the articles themselves (the source text) that constitute the problem. YohanN7 (talk) 14:24, 31 August 2016 (UTC)

Yes, the fact that the article uses two different styles of math formatting makes me question whether "All the mathematical formulas..." can possibly look uniformly wrong. If one set, those using {{math}} or those using <math>, was wrong, then we might be able to propose a fix. I have noticed that, on the mobile interface, <math> tends to render the equations much smaller than the surrounding text. (This is the reverse of how things used to look with PNG rendering on the desktop site.) Sławomir Biały (talk) 15:42, 31 August 2016 (UTC)

Sep 2016

Wikiproject Template discussion

There is a proposal at Templates for Discussion about the math project's talk page assessment templates - the ones that are used for quality and priority assessment. — Carl (CBM · talk) 11:04, 22 August 2016 (UTC)

The template has been relisted for further discussion. See Wikipedia:Templates_for_discussion/Log/2016_August_31#Template:WikiProject_Mathematics. Ozob (talk) 02:15, 1 September 2016 (UTC)

Polygon

Some polygons of different kinds: open (excluding its boundary), bounding circuit only (ignoring its interior), closed (both), and self-intersecting with varying densities of different regions.

This is currently the lead image and caption on the polygon article. As someone who last took geometry over 15 years ago, I'm not sure what a better caption (or image) would be, but (a) The wording is awkward and I'm not sure if the labels are even correct. "Open (excluding it's boundary)" presumably refers to the first image on the left. I thought an open polygon was one that's missing a side. Why would we exclude its boundary? Why would we exclude the interior of the second image? "Closed (both)"... Both what? "self-intersecting with varying densities of different regions" Huh? (b) Even if those examples are correct, are they the best ones to use in the lead image?

I also posted something similar and brought up some other concerns about the wording in the lead on the article's talkpage, but I'm looking for more input from this project as the talkpage doesn't get too much action. —PermStrump(talk) 02:23, 30 August 2016 (UTC)

The answer to "both what" seems clear: both the interior and the boundary. And "open" in this case seems clearly intended to mean that it's it's an open set. As for "one side missing", I've seen the term "polygonal path" used for that, but if the path doesn't return to where it started, then calling it a "polygon" is not something I've seen before. And actually, this set of definitions is not something I've seen before, although their meaning seems clear. Michael Hardy (talk) 02:30, 1 September 2016 (UTC)

Dab pages need checking

I just finished reformatting two mathdab pages: torsion-free and parabolic geometry. I understand the formatting, but not the math involved. I did the best I could with descriptions from the linked articles, but I know some of it isn't right. In particular, I think parabolic geometry (differential geometry) and Cartan parabolic geometry may have a lot of overlap, or might even be identical. Could someone please check those pages and straighten out the descriptions? Thanks. — Gorthian (talk) 22:19, 26 August 2016 (UTC)

Looks good to me. 67.198.37.16 (talk) 21:31, 28 August 2016 (UTC)

Thank you. I'm hoping a couple more people will look, too. — Gorthian (talk) 03:23, 1 September 2016 (UTC)

Chinese remainder theorem

If you have time then please could you have a look at my recent edit to the Chinese remainder theorem article. It was reverted by a Twinkle user because "Unsourced, and the general description of the method is lacking". I added a reference and think the description is quite detailed, so reverted. This has again been reverted. Naturally, I think my edit is fine, but I would like a second opinion. Please see the article's talk page as well. — Fly by Night (talk) 19:34, 1 September 2016 (UTC)

One thing plainly wrong with the new section is that it says "Algebraic Method" with a capital "M" rather than "Algebraic method" with a lower-case "m". Michael Hardy (talk) 23:16, 1 September 2016 (UTC)

Luc Illusie

Hello ! The biography of Luc Illusie (a French mathematician) contained several factual errors, which I corrected directly, while adding new information. But there is a paragraph which I had corrected and which has been re-entered : I think it is at the least very misleading (and not relevant), at the worst almost libellous. At the suggestion of the author of those problematic lines, I explained the problems in this paragraph at length, with references, in the Talk page, Talk:Luc Illusie, but apparently with no success. It would be nice if some of you with good mathematical background (Illusie is an algebraic geometer) can have a look on this discussion and give an opinion. I contributed usually on the French Wikipedia mostly for linguistic reasons. Thank you in advance. Cgolds (talk) 09:22, 2 September 2016 (UTC)

Martin boundary

We have no article titled Martin boundary. Is there someone adept in writing about that? Michael Hardy (talk) 02:53, 2 September 2016 (UTC)

There is an (incomplete and maybe not so well-written) account of the Martin boundary in the page on the Poisson boundary, which could be a start for writing a new page. In case no one wants to do this in the near future a redirect could be a temporary solution. jraimbau (talk) 07:52, 2 September 2016 (UTC)

I've created the redirect and labeled it as being "with possibilities". Michael Hardy (talk) 17:38, 3 September 2016 (UTC)

Dictionary definition of "exponent".

We are having a discussion at wikt:Wiktionary:Requests for deletion#exponent as to whether the existing definitions of the term are overlapping, redundant, or generally correct at all. For reference, we have three mathematical definitions of the word:

1. The power to which a number, symbol or expression is to be raised, for example, the $3$ in $b^{3}=p$.
2. The result of a logarithm, between a base and an antilogarithm, for example, the $4$ in $\log _{b}(a)=4$.
3. (obsolete) The degree to which the root of a radicand is found, for example, the $2$ in ${\sqrt[{2}]{r}}=b$.

The primary question is whether the second sense is redundant to the first. Expert insight would be helpful and appreciated here. Cheers! bd2412 T 14:41, 2 September 2016 (UTC)

See http://www.onelook.com/?w=exponent. —Wavelength (talk) 16:15, 2 September 2016 (UTC)

There is a logical biconditional relationship between $b^{3}=p$ and $\log _{b}(p)=3$, two equations which describe the same relationship in different ways, so they can be called redundant. However, they are different enough that mentioning both of them is informative to a reader who might not easily notice that both of them exist. I prefer that all three definitions cited be included.

—Wavelength (talk) 16:33, 2 September 2016 (UTC)

I agree. --JBL (talk) 16:47, 2 September 2016 (UTC)

Agree (I'm chiming in to show consensus fwiw). SamuelRiv (talk) 17:20, 5 September 2016 (UTC)

Edit warring with User:Pigsonthewing

I unfortunately find myself edit-warring with User:Pigsonthewing, who has been making a number of damaging edits to templates that concern this project. Earlier, he broke Template:nlab and won't let me fix it; Now, he's broken Template:Planetmath reference, with the result that it displays complete garbage. I've reverted, but I don't imagine that this will stick for long. I'm at a loss -- I've seen this kind of hostile behavior in WP far too many times, and I don't understand it's origins. I don't know how to fix it. Anyone? 67.198.37.16 (talk) 07:22, 5 September 2016 (UTC)

In terms of the template I would create Template:Nlab/testcases where you can give an example of the templates use and compare it with a Template:Nlab/sandbox version. That way it will be easier for people to work out quite what has changed. There are different opinions of the syntax for citations, but the current version with full stops does not look right to me. --Salix alba (talk): 09:58, 5 September 2016 (UTC)

There does seem to be a problem. For example, the following entry is at Aristotle#External links, and the link is broken (it uses {{{id}}}):

• {{PlanetMath|urlname=Aristotle|title=Aristotle}} → Aristotle at PlanetMath.

The previous version of {{PlanetMath}} would have generated:

• Aristotle at PlanetMath.org

Johnuniq (talk) 10:37, 5 September 2016 (UTC)

Yes @Pigsonthewing: does seem to have messed things up. I've created the sandbox and testcases mentioned before. For {{Nlab|id=simplex+category|title=Simplex category}} the old Jan 2016 version rendered as

Simplex category in nLab

And the new version as

"Simplex category". nLab.

It is possible to add a mode=cs2 to the call the {{cite web}} which changes the full stop to a comma which is a minor improvement but still looks wrong.

The actual motivation for using {{cite web}} is questionable, these are external links templates not citation templates, and they are different things. I would revert all the changes back. --Salix alba (talk): 11:21, 5 September 2016 (UTC)

I've now reverted changes to {{nlab}}, {{planetmath}} and {{planetmath reference}}. The latter is using the {{cite web}}. {{MathWorld}} is a bit more problematic as it is used either as a reference or an external link, the same seems to apply to {{nlab}} as well, sometimes its an external link, some times its as a reference as in Currying.--Salix alba (talk): 11:56, 5 September 2016 (UTC)

It might be possible to convert the nlab template into an actual "reference", if we could figure out how to provide an author or editor, and maybe a "publisher". Perhaps something like "Urs Schreiber, et al, eds., "Blah Topic", The Nlab wiki." or something like that. Its awkward to figure out quite how to word this, since Nlab itself hasn't given any advice on how to make itself citable (or, at least, I haven't seen any such advice). 67.198.37.16 (talk) 17:34, 5 September 2016 (UTC)

I agree, I don't know of any formal academic citation for nLab. From the nLab FAQ on citing nLab pages, [26] they just mention the preferred form for the url and to be careful of versioning, because the wiki can change over time. --Mark viking (talk) 18:07, 5 September 2016 (UTC)

{{planetmath}} and {{planetmath reference}} are now proposed for merging at Wikipedia:Templates for discussion/Log/2016 September 5. --Salix alba (talk): 19:04, 5 September 2016 (UTC)

Jean-Christophe Yoccoz

Fields Medal winning French mathematician who died on 3 September. He is up for inclusion in the recent deaths section of the main page but has been opposed because the article is a stub that does not reflect his career/research. Can anyone here help out? The combination of French sources and his subject area (dynamical systems) is intimidating. Thanks in advance for any assistance. Espresso Addict (talk) 19:45, 7 September 2016 (UTC)

Rewrite of geometry

I've rewritten the geometry article to be more in line with the changes I made to topology article a couple of years ago. I've used sources to find lists of important topics in geometry, and gathered the previous material into categories such as applications and important concepts. I've shuffled around the old material, and added new, sourced material. I welcome any further changes and refinement (for instance, I did not add polygons as important concepts).Brirush (talk) 20:52, 8 September 2016 (UTC)

Nice! Boris Tsirelson (talk) 05:14, 9 September 2016 (UTC)

Very nice. I like the way of describing the relationship between old and new mathematics (too many WP articles are written as either old mathematics or modern mathematics do not exist). D.Lazard (talk) 08:22, 9 September 2016 (UTC)

Disambiguation of unital

I've wikilinked unital in Hurwitz's theorem (composition algebras). Unfortunately, this is out of my field, and I can't tell which is the correct meaning. Can anyone disambiguate this, please? -- The Anome (talk) 12:11, 9 September 2016 (UTC)

Eulerian coherent structure

Eulerian coherent structure is a fairly new article that could probably use some work. Michael Hardy (talk) 21:07, 9 September 2016 (UTC)

Cyclic function

Sometimes a deleted article is near the borderline between that which should be deleted and that which should be kept, and looks as if some day it could evolve into an article worth keeping. Just in case the one titled "Cyclic function" is such an instance, I've put a copy of it here. One concern is that even if the term "cyclic function" cannot be found in authoritative secondary sources, the topic rather than that particular name of the concept might still be treated in the literature. Michael Hardy (talk) 18:40, 12 September 2016 (UTC)

Family

There's a question at the family talk page under section the genetic overlap table that needs replies or help from a mathematician. Thanks. 92.13.128.131 (talk) 09:09, 13 September 2016 (UTC)

Gennady Andreev

Gennady Andreev.

Is this article worth keeping? Michael Hardy (talk) 16:08, 16 September 2016 (UTC)

Why do you unprod if you're unsure? If the answer is no, it would have been simpler to keep it prodded. —David Eppstein (talk) 17:38, 16 September 2016 (UTC)

Because I was unsure. Michael Hardy (talk) 22:59, 16 September 2016 (UTC)

Harmonic polylogarithm

I wonder if you can get more 2002 than this article, even after my recent edit: Harmonic polylogarithm. Work on it!! Michael Hardy (talk) 05:13, 9 September 2016 (UTC)

This page was deleted in the last 24 hours. Something about a blocked user. !?? 67.198.37.16 (talk) 22:50, 18 September 2016 (UTC)

Besides being created by a sockpuppet Blade Ninja of a blocked user in violation of their block, it was also tagged by R.e.b. as a copyvio of arXiv:hep-ph/9905237. —David Eppstein (talk) 23:35, 18 September 2016 (UTC)

Redirects

Is there policy or guidance on redirects? During editing, I stumbled across redlinks which could have been fixed by redirects. Below is my current list. Could someone maybe create these? (or tell me that its a bad idea?)

• Create redirect exterior connection to Connection form#Exterior connections
• Create redirect contorsion form to contorsion tensor
• Create redirect strict monoidal category to monoidal category
• Create redirect finite transducer to finite state transducer
• Create redirect fibered sum to pushout (category theory)
• Create redirect Künneth spectral sequence to Künneth theorem
• Create redirect mapping fibre to homotopy fiber
• Create redirect mapping fiber to homotopy fiber
• Create redirect locally finite refinement to locally finite collection
• Create redirect weak fibration to Serre fibration
• Create redirect relative homotopy sequence of pairs to Puppe sequence
• Create redirect homotopy sequence of a fibration to Puppe sequence
• Create redirect homotopy sequence of a weak fibration to Puppe sequence
• Create redirect adjoint relation to adjoint functor
• Create redirect structure coefficients to structure constants
• Create redirect quantum deforrmation to quantum group
• Create redirect quantum universal enveloping algebra to quantum group
• Create redirect prequantization to geometric quantization

Thanks. 67.198.37.16 (talk) 15:13, 19 September 2016 (UTC)

These suggestions seem fine. You may create these redirects yourself by registering and editing as a registered user. For a guidance, look at WP:Redirect. D.Lazard (talk) 15:52, 19 September 2016 (UTC)

exterior connection might possibly be better off as a red link since it's a phrase one might use outside of mathematics. --Izno (talk) 16:03, 19 September 2016 (UTC)

If these are created, please tag them with {{R with possibilities}}. —David Eppstein (talk) 17:42, 19 September 2016 (UTC)

Heh. I've got wayyy too many cuts and contusions from editing as a registered user to try that again: the WP community is a snake-pit. Its easier to stay out of the spotlight as an anonymous IP address, excepting occasions such as this. p.s. I think that perhaps universal coefficient theorem needs to be moved to universal coefficients theorem 67.198.37.16 (talk) 17:59, 19 September 2016 (UTC)

@David Eppstein: Why do you want these pages tagged with {{R with possibilities}}? That's for potential templates, and all of these pages would be redirected to articles. RockMagnetist(talk) 17:24, 21 September 2016 (UTC)

{{R with possibilities}} is for redirects that could potentially be made into separate articles, which is exactly what these are. I think you're being confused by reading the expansion of the template itself on the template page (which produces some boilerplate text with the word "template" thrown in) — read the documentation lower down instead. —David Eppstein (talk) 17:48, 21 September 2016 (UTC)

You're right, the documentation says something different, but the template itself says "This is a redirect from a title that potentially could be expanded into a new template". If they really mean "new article", it should be changed. RockMagnetist(talk) 17:55, 21 September 2016 (UTC)

Looking deeper, I see that the code has a conditional, so it says "template" if it's in template space. So it's correct, but very confusing. RockMagnetist(talk) 17:58, 21 September 2016 (UTC)

If a topic is not worth a whole article but is mentioned in some other article, then often a redirect is approrpriate. If it _is_ worth a whole article but none exists yet and you're not going to write one, often it's a good idea to redirect it to another article that says something about the topic. Also, commonplace misspellings or misnomers should be redirected, e.g., theorum redirects to theorem. Michael Hardy (talk) 01:45, 20 September 2016 (UTC)

Wedge product no longer redirects to Exterior algebra

Someone recently broke the redirect of Wedge product to Exterior algebra. I have very mixed feelings about this. Perhaps having an article on the wedge product, only, makes room for a refactored article on the exterior algebra, which could then focus on the algebra, only (just like tensor product and tensor algebra are two different articles). But this refactoring seems like ... well, it will be long and painful, is my knee-jerk reaction. Any other knee-jerk reactions anyone care to have? 67.198.37.16 (talk) 22:47, 18 September 2016 (UTC)

I concur. The wedge product is part of the algebra, and factoring it out would (in my view) to serve two purposes: (a) to reduce the burden (i.e. size) of the article Exterior algebra, and (b) as a kind of stand-alone pedagogical introduction to the term. WP is not really intended for the latter, so the real question whether the Exterior algebra article will benefit from such a refactoring. Since the exterior product is so central to the algebra (as indicated by the Wedge product simply being a copy of the bulk of the lead), I do not see it benefiting from removal of this material into another article. Anyway, whoever did the change did not seem to indicate that this was the intent. —Quondum 23:29, 21 September 2016 (UTC)

Fundamental theorem of linear algebra‎‎

This article does not contain any theorem statement. It is almost an orphan: excepting the template {{fundamental theorems}}, it has very few incoming links. I have tried to replace the poor content of this article by a redirect to isomorphism theorem, but I have been reverted. What to do with this article? More precisely, what is exactly this theorem (it could be the isomorphism theorem or the main property of duality)? Is the name fundamental theorem of linear algebra commonly used (apparently not)? Should we delete this article, merge or redirect it in another article or rename it? D.Lazard (talk) 12:29, 12 September 2016 (UTC)

I believe the theorem is that the kernel of the adjoint of a linear transformation is the orthogonal complement of the image of the linear transformations, and various corollaries obtained by duality. Sławomir
Biały 13:08, 12 September 2016 (UTC)

That is exactly what I meant when talking of duality. D.Lazard (talk) 13:24, 12 September 2016 (UTC)

This is the first time I have heard these results called "fundamental theorem of linear algebra". I think I agree with the sentiment found in this Quora thread; the article should probably be deleted or turned into one aboutthe fact that there is no universally accepted "fundamental theorem of linear algebra". (Personally, I would have expected a "fundamental theorem of linear algebra" not to rely on notions such as orthogonality, but to apply to any finite-dimensional vector space). —Kusma (t·c) 20:37, 23 September 2016 (UTC)

Numerical method

The new article titled Numerical method has perceptible imperfections. Michael Hardy (talk) 03:35, 24 September 2016 (UTC)

Breakthrough on Lyapunov functions?

Recently, Myrocarcassonne (talk · contribs) has added several sections to Lyapunov function, Lyapunov stability, and List of unsolved problems in mathematics describing an apparent breakthrough concerning the construction of Lyapunov functions, using terms like "old problem considered insurmountable by many researchers" that sounded too WP:PEACOCK and WP:WEASEL for me to take it seriously (Update: I deleted the content as a precautionary measure). Further, the only sources for these claims are a 2014 manuscript posted on ArXiv and a self-published 2016 monograph. So, what to do with this? I'm not a mathematician, so hopefully there is someone here with knowledge on the subject. --bender235 (talk) 21:39, 9 September 2016 (UTC)

I do not see a burst of citations of his work. Moreover, I see citations from the author himself only. Boris Tsirelson (talk) 05:13, 12 September 2016 (UTC)

Now 24.146.193.10 (talk · contribs · WHOIS) reverted all my deletions. What to do? Do we keep this stuff or not? --bender235 (talk) 17:41, 12 September 2016 (UTC)

I decided to delete the stuff again per WP:RSSELF. I think, if anything, Myrocarcassonne (talk · contribs) or 24.146.193.10 (talk · contribs · WHOIS) should explain why we should make an exception to this rule in this case. --bender235 (talk) 19:21, 12 September 2016 (UTC)

Update on the latest development: I removed the questionable content from Lyapunov function, Lyapunov stability, and List of unsolved problems in mathematics, but 24.146.193.10 (talk · contribs · WHOIS) kept reverting. I repeatedly asked him to discuss the issue on this WikiProject talk page, but he refused and kept on reverting without explanation. Eventually he was blocked, and all three articles are now semi-protected.

Today I received an email from Myrocarcassonne (talk · contribs) (apparently identical to 24.146.193.10), writing

I am writing you to voice my protest against vicious repetitive deleting the new sections about Lyapunov function added by me and blocking me from further editing and contributing. Deleting was done by the contributor you who is not a mathematician. The discovery of the general method of constructing Lyapunov function has resulted from my previous research works published by Springer. I intentionally put forth the method in a self-publishing way and on Wikipedia with the aim to provide the widest possible consideration not only by mathematicians but also by experts in other branches of the science and technology (physics, chemistry, biology, medicine, economics etc.) where the problems of stability play a very important role. Deleting my sections and blocking me from contributing to Wikipedia go against the freedom of speech, prevent new scientific discoveries from disseminating them among the national and international publics and research communities, hamper the scientific and technological progress. I consider your actions a sabotage of international level. I will take all the measures to make this outrageous fact known to the widest national and international communities.

I'm not going to answer via email, because (i) I don't want this to be a private conversation, and (ii) I want to force Myrocarcassonne (talk · contribs) to finally participate in this discussion here. I will instead answer here:

Dear Myrocarcassonne, your IP alter ego 24.146.193.10 (talk · contribs · WHOIS) has been blocked because you violated WP:3RR despite multiple warnings. Your contributions have been removed because they do not meet Wikipedia's standards for reliable sources. In particular, WP:RSSELF states pretty clearly that self-published material does not suffice as a valid reference. Further, as Boris Tsirelson pointed out, the two references you cite are apparently unrecognized by the mathematical (or any scientific) community; they are not cited or discussed by any other publications than your own. In general, Wikipedia is not a platform to disseminate the latest scientific discoveries. Wikipedia is an encyclopedia.

PS: I'm not sure what you mean by "take all the measures", but you may want to have a look at WP:THREAT.

I hope this will finally receive an answer from Myrocarcassonne. --bender235 (talk) 21:10, 13 September 2016 (UTC)

I agree with bender235. ArXiv is not peer-reviewed (beyond some basic checks for being on-topic) and so cannot be used as a reliable source for a solution to this problem; in addition, we need secondary sources (citations to this work by other people) to say anything about its significance. With an unpublished preprint and no citations, we shouldn't include this material. —David Eppstein (talk) 00:29, 14 September 2016 (UTC)

I agree with bender235 and David Eppstein.--Kmhkmh (talk) 01:00, 14 September 2016 (UTC)

@Myrocarcassonne, Kmhkmh, Bender235, and David Eppstein: There have been additional posts at User_talk:Airplaneman#Lyapunov_Function. This is a content dispute that would best be discussed here, not my talk page. Airplaneman ✈ 19:58, 23 September 2016 (UTC)

I have also looked at the citation numbers for this particular claimed breakthrough, and find very little in the way of secondary sources discussing this work. That does not mean that it isn't revolutionary, merely that it has not (yet?) been noticed in the sense that no reliable third-party independent secondary sources appear to cite this work in a sufficiently in-depth manner to justify inclusion in this article. Unfortunately, it is the policy of Wikipedia to require that such third-party sources must exist in order to merit inclusion. The relevant policies are WP:WEIGHT and WP:NOR. In particular, primary sources typically don't make good sources because it is difficult to assess their weight (in terms of significance), and it is (among other problems) a violation of neutrality for Wikipedia editors to make that decision without explicit independent secondary sourcing. Sławomir Biały (talk) 20:42, 23 September 2016 (UTC)

"Unfortunately, it is the policy" — why "unfortunately"?  :-) Boris Tsirelson (talk) 21:00, 23 September 2016 (UTC)

It is "unfortunate" to someone wishing to see such material covered on Wikipedia, and it may well lead Wikipedia to not containing the most up-to-date information regarding the latest developments. That is also unfortunate; but the community has decided that this possible deficit is by far outweighed by the advantages afforded by adherence to the WP:NPOV and WP:NOR policies. Sławomir
Biały 22:26, 23 September 2016 (UTC)

Dear Wikipedians,

The pasted below is my latest post on Airplaneman's talk page in the scope of our discussion on the Lyapunov Function article and my contribution to it. This is also my answer to his suggestion to continue it here.

"Dear Airplaneman,

Are you serious? You propose me to discuss the topic of Lyapunov Function with the folks

1) who are not experts on Lyapunov Function;

2) who started “their so-called discussion” with me by destroying my work and debarring me from editing. Putting it bluntly, they gagged me and after it Bender235 was intended to “force me” (This is his exact expression) to talk (What is ludicrous after silencing me, isn't it!?) and do what they want. I call this attempt of violence "the communication rape”.

These people behave like communistic or fascistic barbarians, whose prime policy has always been to intentionally destroy any bit of the knowledge challenging their ideas and prevent the information inconvenient for them from the free dissemination among the public. But it is not a free world. It is a totalitarian one in the information sphere.

This is my personal opinion about what is going on with Lyapunov Function article and my contribution to it. " Myrocarcassonne (talk) 19:24, 25 September 2016 (UTC)

Free dissemination of latest results is a good idea; please do it via conferences, journals, forums etc (even youtube is sometimes used by quite serious researchers, to my amusement); but not via encyclopedias (nor museums). Just think calmly on the very notion "encyclopedia"... Boris Tsirelson (talk) 20:24, 25 September 2016 (UTC)

@Myrocarcassonne: maybe you should ease up on the martial vocabulary. And further, as Boris Tsirelson said, keep in mind what an encyclopedia is and is not. In particular, it is not the right place to publish original ideas. --bender235 (talk) 00:05, 26 September 2016 (UTC)

Article for deletion

Article of interest to this project proposed for deletion: Wikipedia:Articles for deletion/Alexandra Bellow. Montanabw^(talk) 07:04, 28 September 2016 (UTC)

Duplicate article?

I think Glivenko's theorem (probability theory), a very recent creation, is the same subject as Glivenko–Cantelli theorem, but I'm not sure enough to do anything about it without checking first. Am I right? — Gorthian (talk) 01:41, 29 September 2016 (UTC)

No. I think that these are different theorems, but this is outside my field. JRSpriggs (talk) 02:03, 29 September 2016 (UTC)

Completely different theorems. Boris Tsirelson (talk) 04:30, 29 September 2016 (UTC)

Okay, thank you! Glivenko was prolific, it seems. — Gorthian (talk) 05:53, 29 September 2016 (UTC)

List of unsolved problems in mathematics

In the List of unsolved problems in mathematics I have taken the liberty of making all the number theory sections into subsections of a single number theory section, and I added "Combinatorial number theory", with just one item. Should we have a new article titled Combinatorial number theory? (Currently that redirects to a section in Number theory, but that section does not currently exist.) Michael Hardy (talk) 00:54, 30 September 2016 (UTC)

Incidentally a lot more of the entries of that list could use sources. Most of the time they can be found by looking at the linked article and finding a recent survey or other representative source for the problem. —David Eppstein (talk) 01:00, 30 September 2016 (UTC)

Oct 2016

Edit war at geodesic

Dangvugiang seems to believe that one of the formulas in geodesic needs an explicit summation, despite the article's explicit statement that it is using the Einstein summation convention. I have already reverted him several times. More eyes would be appreciated. Ozob (talk) 01:46, 1 October 2016 (UTC)

He has also been making extensive changes at Lagrangian mechanics and several other articles, changing notational conventions. See Special:Contributions/Dangvugiang. JRSpriggs (talk) 03:09, 1 October 2016 (UTC)

User:Latex-yow

I wanted to point out this users contributions, which seem to focus heavily on changing the math formatting of articles (sometimes in ways that are improvements, other times in ways that seem pointless). --JBL (talk) 13:11, 3 October 2016 (UTC)

Has there been an instance in which my edits have been negative? Pointless sometimes and improvements sometimes is certainly better than nothing, no? Latex-yow (talk) 15:47, 3 October 2016 (UTC)

Not technical enough

If ever an article needed a "Not Technical Enough" tag, here it is: Abel elliptic functions. Michael Hardy (talk) 02:54, 7 October 2016 (UTC)

Arithmetico-geometric sequence

Hello. A small question for you: I expected an "arithmetico-geometric sequence" to be a sequence of the form $u_{n+1}=au_{n}+b$, but it turns out this only applies to French usage (disclaimer: I'm French), while in English the term Arithmetico-geometric sequence is already taken for something else. Fine. Why not. But then my questions are: 1° What in the world do you call sequences of the form I gave? I just can't seem to find anything to call them in English, and yet that's so simple and obvious an object that it surely must have a name! 2° Do they have a Wikipedia page yet? Compare FR:Suite arithmetico-geometrique. {{u|Gamall ^Wednesday _Ida}}  17:42, 12 October 2016 (UTC)

I am also French, and the only meaning of Arithmetico-geometric sequence (or Suite arithmetico-geometrique) I have heard before was a third meaning. It refers to the sequence of pairs (or intervals) whose limit is the arithmetic–geometric mean. Reliable sources are needed for clarifying the terminology. D.Lazard (talk) 18:11, 12 October 2016 (UTC)

I exhumed my old Terminale S math book; sequences of the form $u_{n+1}=au_{n}+b$ are a staple of Bac problems (or were in the late 90s and early 00s; usually students are given a fixpoint w and asked to show that u_n - w is geometric, etc.), so I was sure to find the term there... annoyingly the book only ever says "suites du type $u_{n+1}=au_{n}+b$". So maybe this terminology is not as universal as I thought. Regardless, such sequences probably deserve an article on the English Wikipedia, the problem is what to call it... {{u|Gamall ^Wednesday _Ida}}  18:48, 12 October 2016 (UTC)

I have tested these terms on Google Scholar: "Arithmetic-geometric sequence": 46 hits; "Arithmetico-geometric": 371 hits; "Arithmetic-geometric mean": 7220 hits. This clearly supports my above comment. D.Lazard (talk) 21:17, 12 October 2016 (UTC)

In fact, the sequences considered in FR:Suite arithmetico-geometrique are generally called linear recurrences of order 1. Note that fr:Récurrence linéaire considers only the homogeneous case. D.Lazard (talk) 21:37, 12 October 2016 (UTC)

Linear recurrences: so that's where they were. I see that the fixpoint technique is dealt with in all generality there. That makes a lot of sense. I have added links to that article in the places where I'd have expected to find them. Thanks for clarifying that. {{u|Gamall ^Wednesday _Ida}}  02:33, 13 October 2016 (UTC)

\bmod does not work.

I have created this.

\bmod does not work in Wikipedia's substitute for TeX. The "b" is supposed to mean "binary", and it should mean that the amount of space before and after "mod" is what is appropriate for a binary operator in mathematical notation. That space does not appear there.

Look at this section (Dominical letter#Formula derived from Gauss's algorithm). Michael Hardy (talk) 06:18, 15 October 2016 (UTC)

It looks OK to me $x{\bmod {y}}$. Whats your browser, OS and maths-preference setting? The help page Help:Displaying a formula#Modular arithmetic suggests using a\,\bmod\,b which creates a little extra space $a\,{\bmod {\,}}b$. --Salix alba (talk): 08:41, 15 October 2016 (UTC)

I see here "mod" and "bmod" ($x\mod y$ and $x{\bmod {y}}$) quite similar to this page. Boris Tsirelson (talk) 10:44, 15 October 2016 (UTC)

I compiled the Gregorian formula in Latex and got the same output as Wikipedia's (SVG, under Chrome linux). The spaces seem fine in both cases. Besides your settings, a screenshot of what you see (or directly the PNG or SVG file if that's what is produced for you) might be helpful. {{u|Gamall ^Wednesday _Ida}}  12:34, 15 October 2016 (UTC)

@Salix alba: It seems to miss the point to say you should code it as a\,\bmod\,b. Look at this:

$5+3\,$

$+3\,$

In the second example you see less space to the right of the plus sign. That's how it's intended to work. It is for that reason that we prescribe the following for non-TeX math notation:

right: 5 + 3

wrong: 5+3

right: +3

wrong: + 3

\bmod is supposed to work like a binary operation symbol such as the plus sign, having some space to its left and right. To say that we have a manual that says we should manually add small spaces is to say "This thing doesn't work right, so you need to manually add small spaces to compensate for the bug." Michael Hardy (talk) 17:43, 15 October 2016 (UTC)

png file

This was coded as y\bmod 4 and looks as if I had written y\text{mod}4 in LaTeX, whereas it ought to look as if I had written y\,\text{mod}\,4 in LaTeX. The spacing should be context-dependent on both sides. Michael Hardy (talk) 18:00, 15 October 2016 (UTC) @Salix alba:

It looks like you have the old PNG/texvc setup. Texvc is a very old unmaintained product and no one knows how to fix it. The best option is to change your preference to "MathML with SVG or PNG fallback", which I think is the default now. I suspect the spacing of \bmod has been a known bug for 10+ years and the a\,\bmod\,b was a workaround to make it work. Now most people are using the MathML/SVG option it should not be necessary. --Salix alba (talk): 18:19, 15 October 2016 (UTC)

Here's another bug: These two lines look identical, whereas they should look different. In other words, \mathbin doesn't work.

${\begin{aligned}&A\Delta B\\&A{\mathbin {\Delta }}B\end{aligned}}$

Might this be the very same bug? Michael Hardy (talk) 18:24, 15 October 2016 (UTC)

Must be a different bug since the SVG backend fails, whereas it works correctly for \bmod. {{u|Gamall ^Wednesday _Ida}}  18:29, 15 October 2016 (UTC)

I've created a new bug T148304 for \mathbin and \mathrel. --Salix alba (talk): 22:03, 15 October 2016 (UTC)

Does 'simple linear regression' imply OLS?

Should the definition of simple linear regression include the use of ordinary least squares (OLS) as the estimation technique, or does the term embrace non-OLS methods (e.g. least absolute deviations)? Interested editors may wish to respond at Talk:Simple linear regression#Title change. Qwfp (talk) 08:42, 18 October 2016 (UTC)

TeX not working

Why is most of the TeX code not getting rendered in this page? Michael Hardy (talk) 21:08, 20 October 2016 (UTC)

Works for me. What browser/OS are you using? --Izno (talk) 21:11, 20 October 2016 (UTC)

TeX seems intermittent for me too. Sławomir Biały (talk) 21:13, 20 October 2016 (UTC)

I too have observed that some TeX-heavy pages are half-rendered on occasion. I'm not sure it's specific to TeX, though; I'm only loading half the images of Bashar al-Assad right now, so it may be general sluggishness. Gamall Wednesday Ida (t.c) 23:18, 20 October 2016 (UTC)

The page returned to normal shortly after I posted this, but for something like a half hour it didn't work. Michael Hardy (talk) 00:45, 22 October 2016 (UTC)

Missing case in geometric series

On the page about Geometric Series, https://en.wikipedia.org/wiki/Geometric_series, for the finite series, the formula for the r<>1 case is given, but not the case for r=1. I believe the correct sum for r=1 is

  s = an

Sorry, but I don't have the skills to do the edit myself. Thanks.

Griswold62 (talk) 13:06, 28 October 2016 (UTC)

@Griswold62: Why not. I have added that case. Gamall Wednesday Ida (t.c) 19:48, 28 October 2016 (UTC)

This discussion belongs on the talk page of Geometric series. I reverted the above edit and gave my reasons for doing so on that talk page. --Bill Cherowitzo (talk) 23:36, 28 October 2016 (UTC)

RFCs on citations templates and the flagging free-to-read sources

See

• Wikipedia:Village pump (proposals)#Access locks: Visual Design RFC
• Wikipedia:Village pump (proposals)#Access Locks: Citation Template Behaviour RFC

Headbomb {talk / contribs / physics / books} 16:25, 29 October 2016 (UTC)

Nov 2016

Wikipedia talk:WikiProject Mathematics/Archive/2016/Nov

Dec 2016

Wikipedia talk:WikiProject Mathematics/Archive/2016/Dec