Wikipedia talk:WikiProject Mathematics/Archive/2018/May

Latest comment: 5 years ago by Arthur MILCHIOR in topic Join (sigma algebra)

Our article on Householder's method is inadequate edit

While we have good articles on Newton's method and Halley's method, our article on the more general Householder's methods is inadequate. In particular, there is no justification given for the claim that the higher order Householder's methods have higher order convergence to a simple root. Without that, I cannot determine what value of K is appropriate and thus how good or bad the method is in particular applications. JRSpriggs (talk) 05:33, 1 May 2018 (UTC)Reply

Weyl Sequence edit

Please could I have an opinion on Draft:Weyl Sequence which I am reviewing at AfC? Should it be moved to mainspace, or is it a duplication of any of these? Curb Safe Charmer (talk) 12:32, 2 May 2018 (UTC)Reply

HTML errors in math articles edit

The wikitext parser is going to change in June, and any page with an error may display strangely. I'm going through Special:LintErrors, and I've found some high-priority errors in articles tagged by this WikiProject.

What's needed right now is for someone to click these links and compare the side-by-side preview of the two parsers. If the "New" page looks okay, then something's maybe technically wrong with the HTML, but there's no immediate worry. If that column looks wrong, then it should be fixed.

This list is all "misnested tags". See mw:Help:Extension:Linter/html5-misnesting for more information. Taking the first link as an example, there is highlighting in the wikitext that shows where the lint error is; it's in the {{cot}} template. My first guess is that this template adds span tags, which don't work over multiple paragraphs. The second column shows some additional information about the error (please let me know if that's useful additional information).

https://en.wikipedia.org/wiki/Homomorphism?action=parsermigration-edit&lintid=83561193 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Lambda_calculus?action=parsermigration-edit&lintid=87630999 {"name":"cite","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Vector_space?action=parsermigration-edit&lintid=89781937 {"name":"cite"}
https://en.wikipedia.org/wiki/Conjugacy_class?action=parsermigration-edit&lintid=45688989 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Triangle_inequality?action=parsermigration-edit&lintid=47827125 {"name":"span","templateInfo":{"name":"Template:About"}}
https://en.wikipedia.org/wiki/Ampersand?action=parsermigration-edit&lintid=80068708 {"name":"span","templateInfo":{"name":"Template:Infobox_grapheme"}}
https://en.wikipedia.org/wiki/Skewes's_number?action=parsermigration-edit&lintid=88355187 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Rank–nullity_theorem?action=parsermigration-edit&lintid=68455718 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Incidence_structure?action=parsermigration-edit&lintid=75276042 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Apéry's_constant?action=parsermigration-edit&lintid=92507466 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Homography?action=parsermigration-edit&lintid=46804131 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Schuette–Nesbitt_formula?action=parsermigration-edit&lintid=45593631 {"name":"span","templateInfo":{"name":"Template:NumBlk"}}
https://en.wikipedia.org/wiki/Law_of_cosines?action=parsermigration-edit&lintid=75766991 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Effective_complexity?action=parsermigration-edit&lintid=47682793 {"name":"span"}
https://en.wikipedia.org/wiki/Sanford_L._Segal?action=parsermigration-edit&lintid=46514210 {"name":"span","templateInfo":{"name":"Template:Infobox_scientist"}}
https://en.wikipedia.org/wiki/Derivative_of_the_exponential_map?action=parsermigration-edit&lintid=74204860 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122874 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122875 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122876 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122877 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122878 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122879 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122880 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Superparabola?action=parsermigration-edit&lintid=50122881 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}
https://en.wikipedia.org/wiki/Gianfranco_Cimmino?action=parsermigration-edit&lintid=92300744 {"name":"span","templateInfo":{"multiPartTemplateBlock":true}}

Note that the highlighting from the lintid code won't work reliably after the article has been edited, so for pages with multiple errors, it's best to try to fix them all at once. For more help, you can ask questions at Wikipedia talk:Linter. Good luck, Whatamidoing (WMF) (talk) 17:53, 4 May 2018 (UTC)Reply

Looking at Apéry's constant, the entire citation section is highlighted. This is unhelpful in finding a problem. Is it the {{math}} templates in article titles? There is no good reason why that shouldn't continue to work. —David Eppstein (talk) 18:35, 4 May 2018 (UTC)Reply
It appears that the problem is in {{Citation | title = The Apéry's constant: {{math|ζ''(3)''}} }}. It looks like the problem goes away if you remove the italics from math template, which is inside an already-italicized title field. Whatamidoing (WMF) (talk) 19:22, 4 May 2018 (UTC)Reply
This is more a problem of the cite templates than it is a problem with the page sources here. I need to get around to poking Help talk:CS1 about it. --Izno (talk) 19:55, 4 May 2018 (UTC)Reply
Ok, the problem is a general one with the {{math}} template series: it doesn't work when the surrounding context is already italicized (because then the sense of what should be italicized or not inside the template is wrong). In fact, it was always wrong but the new html verification actually catches the error, which is an improvement. And it's not really related to cite templates; the same thing happens if you try to use {{math}} inside {{unsolved}}. One fix is to use <math> instead in such contexts, as one of the Apéry references already does. —David Eppstein (talk) 20:59, 4 May 2018 (UTC)Reply

Duodecimal edit

I'm trying to figure out what is going on, what that IP editor from Taiwan has been doing the last few months (also on the talk page). Thanks, Drmies (talk) 21:48, 4 May 2018 (UTC)Reply

It's a mix of trivia and numerology. There are lots of numbers, and if you do math in the right ways, they sometimes have mildly amusing patterns in the results. power~enwiki (π, ν) 23:49, 4 May 2018 (UTC)Reply

Draft:Core-Sérsic profile edit

I wonder if somebody would be kind enough to have a look at the above draft, which is currently sitting at Articles for creation. My question is whether it has sufficient Notability/content to warrant its own article, or whether the content could/should be merged in to the existing article, Sersic profile? Any comments gratefully received. If anybody who looks at it happens to be an Afc reviewer, they can, of course, Accept it as an article should it be warranted. Best regards. KJP1 (talk) 05:40, 6 May 2018 (UTC)Reply

This list is too short edit

The article List of mathematical identities is suspiciously short. May anyone help expanding it? --MaoGo (talk) 23:53, 5 May 2018 (UTC)Reply

"External links" there lead to much longer lists. How many of these do you like to see here? Boris Tsirelson (talk) 05:43, 6 May 2018 (UTC)Reply

Cleanup of G-structure on a manifold edit

I'd like to clean up the article G-structure on a manifold. Is the proposal here Talk:G-structure_on_a_manifold#Merge_cleanup_proposal ok? --TurionTzukosson (talk) 10:51, 9 May 2018 (UTC)Reply

Standard for Math abbreviation? edit

Over the past few months, I've added support for both Bluebook abbreviations (in law), and MEDLINE abbreviations (in medicine) to {{Infobox journal}} and to the WP:JCW compilation. What's the standard, so to speak, for abbreviations in mathematics? MathSciNet? Headbomb {t · c · p · b} 00:00, 10 May 2018 (UTC)Reply

Gonna @David Eppstein: here. Headbomb {t · c · p · b} 00:00, 10 May 2018 (UTC)Reply
The standard for how to abbreviate journal names, you mean? That would be however MathSciNet abbreviates them, I think. (Or maybe Zentralblatt MATH, if that ever differs from MathSciNet). —David Eppstein (talk) 00:15, 10 May 2018 (UTC)Reply
Is there a list (preferably public) of such abbreviations? Or a per-journal information page e.g. [1]? Headbomb {t · c · p · b} 00:20, 10 May 2018 (UTC)Reply
There are per-journal information pages e.g. Ann. of Math. but I suspect you need a subscription to find them and/or access them. (I'm currently editing on a machine with subscription access so I can't tell.) Under "free tools" they list current journals which will give you a list of the journals from which they have recently added publications, but that's not going to be the complete list of all journals indexed. —David Eppstein (talk) 00:46, 10 May 2018 (UTC)Reply
Yeah, it's paywalled. I think I have access at work, but I'm not sure (I'll check tomorrow). The point would be convenience links for verification, so a paywall links beats nothing in that it be useful to some people, even if it's nowhere near ideal. I wonder if anyone here has any clout within the AMS to convince them to open up some of the database at least. Headbomb {t · c · p · b} 00:58, 10 May 2018 (UTC)Reply
Are you looking for Abbreviations of Names of Serials? It is a PDF, but might be a start. --Mark viking (talk) 03:09, 10 May 2018 (UTC)Reply
@Mark viking: That's a fantastic ressource, albeit in a crappy format. However, I could probably convert this to a bot-friendly format, and would definitely make a better link than a paywall. Headbomb {t · c · p · b} 03:19, 10 May 2018 (UTC)Reply

The reason for abbreviating names of journals does not apply to Wikipedia, but it has been used out of habit. I prefer not to abbreviate them. Michael Hardy (talk) 22:01, 10 May 2018 (UTC)Reply

We may still need the list to reverse the abbreviations and get the full name of the journal. JRSpriggs (talk) 00:56, 11 May 2018 (UTC)Reply
Yes, and it's also useful to mention the abbreviations in the articles about the journal (or in the infobox of the article). —David Eppstein (talk) 01:24, 11 May 2018 (UTC)Reply

Alright, {{Infobox journal}} now supports |mathscinet= for when the abbreviations differ from the ISO 4 one. See Annals of Mathematics. The infobox will prompt you to create redirects when you add the relevant abbreviation, just like it does for the ISO 4 one. Headbomb {t · c · p · b} 13:19, 11 May 2018 (UTC)Reply

Please comment above. This concerns the usage of MathSciNet abbreviations in {{infobox journal}}. Headbomb {t · c · p · b} 16:25, 11 May 2018 (UTC)Reply

Draft:Non-manifold topology needs review edit

Could somebody take a look at Draft:Non-manifold topology and give a review. It's a technical article that really requires a SME to evaluate. -- RoySmith (talk) 18:09, 11 May 2018 (UTC)Reply

This is terribly written but apparently it is about a legitimate topic, though more pertinent to computer science/engineering that mathematics. As far as I can tell a "non-manifold topology" as described there is just and embedded 2-complex in Euclidean space and the article describes ways to implement and compute with these things. In this state I think the article should probably not be allowed in main space (quite unintelligible, too many imprecisions and badly organised and formatted) but I guess minor rewrites and re-organising it would make it acceptable. I'm not familiar enough with this kind of applications to do it myself, perhaps asking for a reviewer at WikiProject Computer science would make sense. jraimbau (talk) 11:59, 12 May 2018 (UTC)Reply

I've done some edits to make it conform to some basic Wikipedia conventions, but I haven't addressed the actual content. It contains this sentence:

Non-manifold is a geometric topology term that means 'to allow any combination of vertices, edges, surfaces and volumes to exist in a single logical body'.

So an adjective is defined as a verb? Obviously someone isn't all that great at writing complete sentences. Michael Hardy (talk) 17:42, 13 May 2018 (UTC)Reply

He seems to be talking about something similar to what we would call a Simplicial complex. JRSpriggs (talk) 02:02, 14 May 2018 (UTC)Reply
Yes, but the pieces need not be simplices. My understanding is that this term is used e.g. in finite element simulation to describe models (such as, say, the mechanical behavior of a car body) that are lower-dimensional than the ambient space but do not form manifolds in that space. In mathematics, you would just say a cell complex, but in these other areas the assumption that a 2d model has to be a manifold is stronger, so you have to qualify the things that aren't. —David Eppstein (talk) 02:47, 14 May 2018 (UTC)Reply

Visualisation of functions, infobox edit

I think about making two kinds of related edits to some standard functions. I prefer to ask your opinion in order to be sure not to lose my time. Those edits are related to the presentations of some of the standard mathematical functions. Complex one and real ones.

Firstly, I think that Category:Visualization_(graphic) should have a subcategory «mathematical function representation». Indeed, when I look at a page such as Heat map and want to learn more about visualization of functions, I do expect to find pages like Domain coloring. But I do not expect to find IEEE Visualization. Both of those pages have category "Visualization_(graphic)". I guess this means that heat map and domain coloring should have a more precise category. This category would also include surface plot e.g.

By the way. Do anyone know if there is a «surface plot» somewhere on wikipedia. One which consider representing a function by plotting its surface. Becase currently, surface plot consider only radar related plot. And so, Heat map link to surface plot is probably wrong, however I do not know how to correct this link. I would create the page if you tell me that it does not exists yet.

Which lead me to my second point. What do you think about having a infobox for standard functions. This v would, as far as possible, contains the representation of the function using as many visualization technic as possible. (It would not be hard to generate them using some mathematical library. So there are no copyright problem to have them). I guess that the infobox should also contain standard information, such as the domain of definition (or the more standard one, e.g. for square root and log, where many domain can be chosen), its derivative (or jacobian), its antirderivative, the domain on which it is continuous, differentiable, etc...

Of course, some of those informations are already in the page of the functions. But I do believe that having a more standard presentation would help me. Since I guess I'm not alone, I assume it would also help other readers. — Preceding unsigned comment added by Arthur MILCHIOR (talkcontribs)

(Slightly off-topic comment) Make sure to use sentence case when wikilinking to existing articles. When we refer to an article by its name (such as Domain coloring), we use upper case, but when we talk about domain coloring, we must use sentence case—see Wikipedia:Manual of Style#Wikilinks. Also, we should avoid using first-person pronouns in articles—see MOS:WE. I made a slight change to your edit: [2]. Cheers. - DVdm (talk) 22:31, 18 May 2018 (UTC)Reply
First, have you seen the statistics pages on distributions such as the normal distribution? Each one has an infobox with graphs of the PDF and CDF and summaries of the most basic facts. You want to do something similar for "all" functions on Wikipedia? Actually, we already have similar infoboxes for some mathematical functions, such as sine. How does that infobox compare to what you want?
Indeed, statistic infobox gave me the idea. No, I don't intend to do it myself for every single function. I did intend to do it for the most common one, the one from which the informations are easy to find. Furthermore, I wouldn't intend to draw representation if they are hard to compute. I did look at pages such as trigonometric functions, where I didn't see any infobox. I didn't see the page sine existed. In fact, I always wrote sin, and din't even know that «sin» existed. I guess that, what I want is to add more parameters to this infobox, in order to put the information I mentionned above. There is no reason to have two distinct infobox. (Note that it means that we would need to draw both the sine function as a real function, and as a complex funciton.) Arthur MILCHIOR (talk)
I agree that we should strive for one infobox on a page, not two. How do you intend to visualize sin : C -> C? The graph is four-dimensional. Show how a grid on the domain appears deformed in the codomain? Plot the real and imaginary parts using colors or contours? There are many options. Mgnbar (talk) 15:47, 19 May 2018 (UTC)Reply
I fear I had not been clear, because I thought I already answered this. There are a few standard way to represents C->C functions. Two of them are mentionned above: domain coloring and heat map. There are also integral curve and vector field. I imagine there are other representations I do not know. Of course, each such visualization represents exactly the same thing. But in a different way. I do not have any data allowing me to know which representation is more intuitive/is easier to understand for someone reading this page. So I kind of assume that having all of them available, and letting the reader look at the one they prefer is the best option.
I saw you told me below to be bold. I know this rule. I usually follow it, at least when I create/edit pages about graduate-level subject I do know. However, since I'm considering a dozen page, some of them which are mathematically really important, I thought that trying to obtain a consensus beforehand. — Preceding unsigned comment added by Arthur MILCHIOR (talkcontribs) 18:25, 19 May 2018 (UTC)Reply
Second, you mention that surface plot is about radar. But have you seen graph of a function?
No, I didn't see it. Thank you. I guess the first page should have a disambiguation to the second one. Arthur MILCHIOR (talk)
It sounds good to me. Wikipedia:Be bold. Mgnbar (talk) 15:47, 19 May 2018 (UTC)Reply
Third, there are many functions in mathematics. You seem to be focused on functions R -> R and R^2 -> R (where R is the real numbers). Is that right? Mgnbar (talk) 13:18, 19 May 2018 (UTC)Reply
Partly right. Concerning the question of drawing those functions, you are almost right (Assuming that C = R^2). In my example, I would want to represent sin as a function from C to C. Functions from higher dimension would be harder to draw, I don't really know standard way to do it. However, I also wrote about Jacobians. So I assume that this part would still be relevant for a R^n-> R^m function.
Thank you for taking the time to answer my questions. Arthur MILCHIOR (talk)
That's what I was getting at. Visualization is possible only for the lowest dimensions, and even low dimensions require tricks or suffer from imperfections. And that fact might make it harder for you to build consensus for a standardized way to treat all functions. But it's worth discussing. (By the way, visualizing a function by how it deforms a grid in its domain is a good way to visualize the Jacobian.) Mgnbar (talk) 15:47, 19 May 2018 (UTC)Reply

Just to report a strong impression I got here at WP: The acceptance of infoboxes at the valuable real estate at the header of an article might be equivocally. Purgy (talk) 18:53, 19 May 2018 (UTC)Reply

I must admit, Purgy Purgatorio, that I do not understand the last message. English is not my mother tongue. I can guess that you mean that some people does not like infoboxes. That sometime, they should be avoided. Anyway, if you have a link, with a place where this subject was discussed, it would help me understand the pro and the con of my idea. Regards. Arthur MILCHIOR (talk) —Preceding undated comment added 10:33, 20 May 2018 (UTC)Reply
(Another meta-comment) Please sign all your talk page messages with four tildes (~~~~)—see Help:Using talk pages.
Also, please do not write your comments inside other's comments. I.o.w., always go to the bottom—see WP:THREAD. Thanks. DVdm (talk) 18:53, 20 May 2018 (UTC)Reply
You guessed about right. I am uninvolved in these debates, but admit being skeptic wrt general application of infoboxes. Just by chance (me being torn before WP:AN(/I)) I noticed a ferocious discussion. You might search there and will find some quarrels about "infobox", like this about "ownership", and also later ones. Purgy (talk) 06:41, 21 May 2018 (UTC)Reply

Merging proposal edit

A proposal has been submitted to merge Category:Probability journals into Category:Statistics journals. Please add relevant arguments to the discussion. Marcocapelle (talk) 06:29, 25 May 2018 (UTC)Reply

Probability and statistics are often taught in different departments; the first always in the mathematics area and the other either as a standalone field or part of applied math or sciences, sometimes even in economics. That should give us an idea of the demarcation. Limit-theorem (talk) 08:34, 25 May 2018 (UTC)Reply

Should John von Neumann be categorized as a combustion scientist? edit

See Talk:John von Neumann#Should_von_Neumann_be_categorized_as_a_combustion_scientist? Paul August 10:31, 25 May 2018 (UTC)Reply

No more than Einstein as a nuclear scientist. Boris Tsirelson (talk) 10:55, 25 May 2018 (UTC)Reply
Boris, would you please add your remark to the discussion at Talk:John von Neumann? Paul August 11:21, 25 May 2018 (UTC)Reply
Please add further discussion to the discussion at Talk:John von Neumann. Thanks. Paul August 11:23, 25 May 2018 (UTC)Reply

Category:Jewish mathematicians edit

Kyuko has recently created Category:Jewish mathematicians and added several hundred articles to it (and going strong; the only interruption has been this edit). I do not have any principled opinion about whether this is good or bad, but possibly other editors might. --JBL (talk) 13:38, 24 May 2018 (UTC)Reply

As long every targetted article subject is described as Jewish, with a proper source. The first (and only) example I checked is Georg Cantor. The article says that "Cantor was sometimes called Jewish in his lifetime." (with a source). That is definitely not sufficient to categorize Cantor as a Jewish mathematician. So I have reverted that one. I suspect that there are dozens—if not hundreds—of similar examples, but I have no time to check more articles. I'd support removal of the category. - DVdm (talk) 14:16, 24 May 2018 (UTC)Reply
Note, I also just checked Hermann Minkowski. The article says that he was of Jewish descent, which i.m.o. is again not sufficient. No time for more at this point. This might need a stop and an administrative mass revert. - DVdm (talk) 14:31, 24 May 2018 (UTC)Reply
I've dropped a line on Kyuko's talk page in case they didn't get the ping. Reyk YO! 14:36, 24 May 2018 (UTC)Reply
Thanks, Reyk. DVdm, I see someone else has reverted on Deborah Tepper Haimo (twice!), where the article makes no mention of either religion or ethnicity. --JBL (talk) 14:40, 24 May 2018 (UTC)Reply
With respect to Cantor article, it writes that "In a letter written by Georg Cantor to Paul Tannery in 1896 (Paul Tannery, Memoires Scientifique 13 Correspondence, Gauthier-Villars, Paris, 1934, p. 306), Cantor states that his paternal grandparents were members of the Sephardic Jewish community of Copenhagen" (with a reference). The Minkowski article likewise provides a source. --Kyuko (talk) 14:45, 24 May 2018 (UTC)Reply
As for the category itself, there are already a number of categories for mathematicians of various ethnicities / nationalities, I see no reason why this would be any less valuable to Wikipedia. --Kyuko (talk) 14:47, 24 May 2018 (UTC)Reply
It's also worth mentioning that there's already an extensive Category:Jewish physicists. --Kyuko (talk) 14:50, 24 May 2018 (UTC)Reply
There's a Category:Mathematicians by ethnicity with an odd assortment of 'ethnicities' in it which this is a subcategory of. And a larger one of Category:People by ethnicity and occupation. The criterion for them as best I can make out is that be at least a few entries but not too many, they strike me as a bit strange. Dmcq (talk) 14:48, 24 May 2018 (UTC)Reply

A category called "Jewish mathematicians" must be reserved for those who have explicitly declared their own adherence to Judaism, while a category called "Mathematicians of Jewish descent" can include all those for whom reliable sources indicate Jewish ancestry. See WP:BLPCAT and WP:CAT/R. XOR'easter (talk) 15:16, 24 May 2018 (UTC)Reply

I'd certainly be open to changing the name of the category. At the risk of going into a discussion on who is a Jew, though, discounting as Jews all those who have not publicly "declared their own adherence to Judaism" is absurd; "Jewish" is an ethnic designation as much as it is a religious one (see e.g. List of contemporary ethnic groups) and so WP:BLPCAT is not relevant here. There is, moreover, precedent for such categories (see e.g. Category:Jewish physicists, Category:Jewish chess players, Category:Jewish philosophers, Category:Jewish American musicians, etc. etc.). --Kyuko (talk) 16:27, 24 May 2018 (UTC)Reply
I am in complete agreement with XOR'easter. WP:BLPCAT is very explicit that we can only categorize someone as having a particular religion when that person explicitly and publicly declares it to be their religion. Past violations by others are no excuse for your own massive violations of this rule. —David Eppstein (talk) 16:30, 24 May 2018 (UTC)Reply
Again, the category is meant in reference to a particular ethnic group (as indicated by its inclusion in Category:Mathematicians by ethnicity). I am open to changing the name to reflect this, but mass-deleting instances of the category is unhelpful. --Kyuko (talk) 16:34, 24 May 2018 (UTC)Reply
Easy way to handle this issue, change the category to Category:Jewish mathematicians and mathematicians of Jewish descent. It would be reasonable to modify the above mentioned categories for physicists and the like in the same way. JoshuaZ (talk) 17:04, 24 May 2018 (UTC)Reply
Great idea - done! --Kyuko (talk) 17:32, 24 May 2018 (UTC)Reply
Even for the mathematicians of Jewish descent, we cannot include people in that category without published reliable sources about their Jewish ancestry. So this change reduces the size of the problem created by Kyuko's edits but does not eliminate it. By the way, I'm sure many Palestinian Israeli citizens would be surprised to learn that, according to Kyuko, they are all now Jews. This illustrates the danger of uncareful categorization. —David Eppstein (talk) 17:45, 24 May 2018 (UTC)Reply
That edit was a mistake - mea culpa. But this is clearly something personal and political for you, seeing as it's not your first time going through Wikipedia deciding who is and isn't a Jew by your criteria. In any case, are you even checking the pages to see if there are sources given before mass-deleting all instances of the category? There's no world in which e.g. Paul Cohen or Alexander Grothendieck aren't of Jewish descent. --Kyuko (talk) 17:56, 24 May 2018 (UTC)Reply
I mass-rollbacked the changes I saw because you are clearly being indiscriminate in who you are adding and it is a waste of my time to be the one to check the edits carefully when you are not doing it yourself. Your most recent edits to Tamar Ziegler are very illustrative — edit-warring to violate WP:BLP like this has as its most likely outcome you getting blocked. And your comment here comes perilously close to being a personal attack; please be more careful in that as well. —David Eppstein (talk) 18:08, 24 May 2018 (UTC)Reply
[edit conflict] 1. It is an extremely poor idea to go around accusing others users of bias. 2. It is silly for a person in your position, just having made a huge number of edits without checking whether they are individually supportable, to complain about others reverting your edits without checking each one individually. 3. The criterion here ("supported by reliable sources") is a standard one on WP; if you don't understand it, maybe you shouldn't be editing here. --JBL (talk) 18:11, 24 May 2018 (UTC)Reply
I'm going through each article individually now and adding back the category to those which provide support (or adding sources where possible) -- my intention is not to edit-war. Regarding the articles, nearly all were compiled from previously-existing lists on Wikipedia (e.g. List of British Jewish scientists, List of Jewish American mathematicians, List of Jewish mathematicians, List of German Jews, List of Jews born in the Russian Empire and the Soviet Union, etc.). In retrospect I should have fact-checked each one (I now plan on doing so), but in any case I was not being indiscriminate in who I added. --Kyuko (talk) 18:26, 24 May 2018 (UTC)Reply
Is this a re-creation? I'm pretty sure there used to be a "Jewish mathematicians" category, which means that if it was recently created, then at some point it must have been deleted. Paging User:BrownHairedGirl, who should know how to look this up.
If it was previously deleted, that's not necessarily an absolute bar to re-creation, but at least the previous decision should be understood and the points addressed. --Trovatore (talk) 18:31, 24 May 2018 (UTC)Reply
I removed the last 15 stray entries. - DVdm (talk) 19:19, 24 May 2018 (UTC)Reply
The renamed category is not the same category, and so shouldn't be subject to speedy deletion by itself. JoshuaZ (talk) 23:45, 24 May 2018 (UTC)Reply
I am inclined to agree with JoshuaZ. Also, the previous discussion was a decade ago, it is totally possible consensus would be different now. --JBL (talk) 12:08, 25 May 2018 (UTC)Reply
I think the second point is the key one. Clearly if the new category had been created on May 21, 2007, it would have been seen as a threadbare attempt to get around the deletion decision and speedily deleted.
According to current theory and practice, I think the remedy for deletions you don't agree with is supposed to be DRV, but this seems not quite adequate, because DRV is supposed to overturn decisions that were procedurally flawed in some way, or where the closer misjudged consensus. But I don't think we really want to say that a procedurally impeccable deletion is final for all time. This seems like an issue that needs a more general solution; I don't know what it is.
As to this category, I do kind of hope that it stays deleted, because if I never have to read another argument about whether Cantor was Jewish, it will be too soon. --Trovatore (talk) 18:00, 25 May 2018 (UTC)Reply

WikiProject collaboration notice from the Portals WikiProject edit

The reason I am contacting you is because there are one or more portals that fall under this subject, and the Portals WikiProject is currently undertaking a major drive to automate portals that may affect them.

Portals are being redesigned.

The new design features are being applied to existing portals.

At present, we are gearing up for a maintenance pass of portals in which the introduction section will be upgraded to no longer need a subpage. In place of static copied and pasted excerpts will be self-updating excerpts displayed through selective transclusion, using the template {{Transclude lead excerpt}}.

The discussion about this can be found here.

Maintainers of specific portals are encouraged to sign up as project members here, noting the portals they maintain, so that those portals are skipped by the maintenance pass. Currently, we are interested in upgrading neglected and abandoned portals. There will be opportunity for maintained portals to opt-in later, or the portal maintainers can handle upgrading (the portals they maintain) personally at any time.

Background edit

On April 8th, 2018, an RfC ("Request for comment") proposal was made to eliminate all portals and the portal namespace. On April 17th, the Portals WikiProject was rebooted to handle the revitalization of the portal system. On May 12th, the RfC was closed with the result to keep portals, by a margin of about 2 to 1 in favor of keeping portals.

There's an article in the current edition of the Signpost interviewing project members about the RfC and the Portals WikiProject.

Since the reboot, the Portals WikiProject has been busy building tools and components to upgrade portals.

So far, 84 editors have joined.

If you would like to keep abreast of what is happening with portals, see the newsletter archive.

If you have any questions about what is happening with portals or the Portals WikiProject, please post them on the WikiProject's talk page.

Thank you.    — The Transhumanist   07:47, 30 May 2018 (UTC)Reply

Join (sigma algebra) edit

Could someone with five minutes of free time and nothing better to do take a look at the history of Join (sigma algebra) and see if the massive trimming down was legitimate? – Uanfala (talk) 21:10, 29 May 2018 (UTC)Reply

The trim seems not unreasonable given the talk page discussion, as a WP:TNT approach to a flawed discussion. Bringing the prose back and fixing it would an improvement. --Mark viking (talk) 21:18, 29 May 2018 (UTC)Reply
So the question is, how much is there to say about joins of sigma-algebras? Right now the article is a DICDEF. If there's nothing more to say than the definition, then the article should probably be merged into a glossary somewhere. --Trovatore (talk) 22:53, 29 May 2018 (UTC)Reply
Note that Join is actually explained in the Sigma-algebra page. Therefore, I went bold, and used a redirect from the join page to the section in which this notion is introduced — Preceding unsigned comment added by Arthur MILCHIOR (talkcontribs) 14:12, 30 May 2018 (UTC)Reply