Talk:Massless particle/Archive 1

Merge

I think this article should be merged with Mass in special relativity for the following reasons:

• The concept Luxon is hardly used anywhere. Actually I have never seen it before.
• The meaning is completely identical to that of a massless particle.
• Much of the content of the article actually doesn't belong here. Gauge boson information should be (and most is) at Gauge boson, gravitino information at Gravitino, etc. Here it's just eclectic pieces of information which don't make up a coherent article.

Dan Gluck 12:22, 7 July 2007 (UTC)

NO.
Point 1. The fact that you haven’t come across terms like Luxon many times means very little. It is a mistake to try to make physics to coherent - it isn’t a coherent body. 'Luxon' is one of a series of very generic terms relating to classification of velocity realm. (ie Tachyon, Luxon and Tardon).
Point 2. A Luxon is any particle that moves at the speed of light. Some Luxons may have mass some don't, it specifically doesn't specify mass - only velocity.

Much of the work on Relativity in recent years (decades) has gained a kind of totalitarian flavour that tries to suppress anything that contradicts it even slightly and in the process often hides its own weaknesses. You may deny the existence of tachyons, but it is important to keep the concepts in use. (Personally as an adherent of hyperspace theory I find tachyon and Luxon rather important definitions.)
Lucien86 21:15, 19 September 2007 (UTC)

Your (or my) personal likings are irrelevant. What does matter is the physics community, which regards what you write here as nonsense. Relativity is a complete consensus among physicists. Dan Gluck 20:21, 22 September 2007 (UTC)

I have a PhD in particle physics and regularly publish in the field - I've never heard this term (perhaps not important) nor can I find it in any of the standard high energy texts or via google search. I suppose anyone could define a "fill-in-the-blank-with-randon-word" and call it a label for particles that move only at the speed of light ... but why put it in wikipedia? —Preceding unsigned comment added by 75.70.70.90 (talk) 05:02, 25 November 2007 (UTC)

You will find some pages, if you use keywords "luxon particle". I am also a physicist. Why not to put it in Wikipedia? Why put anything in Wikipedia? Urvabara (talk) 19:04, 26 November 2007 (UTC)

'Luxons'? 'bradyons'? wtf? These are hardly well-established, standard notions of the kind belonging in an encyclopedia. Any student using terms like 'bradyon' in a homework is going to get marked down. 81.101.44.107 (talk) 02:52, 20 December 2007 (UTC)

Actually I have changed my mind and in favor of deleting it.Dan Gluck (talk) 18:05, 20 December 2007 (UTC)

I think some of this article is salvageable as an article named "Massless particle", which currently does not exist, the closest approximation being Relativistic particle. I will boldly carry out this change without further discussion. Melchoir (talk) 20:33, 2 January 2008 (UTC)

Hi I really agree now on the terminology thing, some of my sources were quite exploratory and may have been using their own personal terminology. However, '...write here as nonsense. Relativity is a complete consensus among physicists.' not that its relevant but this doesn't say a great deal for the intelligence of the physics community, myself as an amateur found gaping holes in the theory within a short time of actually trying. On taking a more and more thorough approach some holes closed but even worse ones open(ed). - Relativity has to allow 'time' to travel at infinite velocity otherwise it can't handle non-locality, but this allows a direct and complete mapping of classical hyperspace. Not only is this model clearly much better, but it beats Relativity on Occam's razor as well because it is much simpler. What it also showed me though is that the more you try to break Relativity the stronger its heart becomes. Lucien86 (talk) 05:04, 20 December 2008 (UTC)

BTW on massless particles I assume that a massless particle must also have zero energy - because of mass energy equivalence, maybe that's not a comfortable question either. Lucien86 (talk) 05:04, 20 December 2008 (UTC)

Slight change

I made a slight change in the first paragraph regarding the gluons to use more hypothetical language, since later on in the article it explicitly says that there has never been any experiemental evidence that suggests the existence of a gluon. If the gluon has been discovered and I didn't notice, it can be changed back, but at least at the moment the article is internally consistent. (Previously it said something along the lines of "gluons are always contained within hadrons", then lower down it says "gluons may or may not exist.") — Preceding unsigned comment added by 125.238.237.250 (talk) 01:17, 7 August 2014 (UTC)

The existence of gluons is not disputed. They haven't been observed as free particles, but no one doubts their existence. Headbomb {talk / contribs / physics / books} 05:51, 7 August 2014 (UTC)

Slight change

I removed the part of the sentence in the Special Relativity section which claims that massless particles don't experience time. I have a PhD in particle physics, and I know that certain astrophysicists have made this claim, but it does not make any sense. The main reason, as I have understood it, that people are making this claim is that they take the limit of the Special Relativity equations for massive particles to the limit that v=c. It is important to understand that this is not a limit that makes sense to take. Photons are not defined as the limit of what happens to a massive particle as m->0 and v->c. Photons, in particular, have dynamics that are described by a separate set of field equations than massive particles from the perspective of Quantum Field Theory (which is our most fundamental tool to understand the particles/fields in nature), so no connections of that kind should be implied. Furthermore, in Special Relativity there is no inertial frame of reference that moves at the speed of light, therefore it is meaningless to talk about measuring the time or distance between events from the perspective of the massless particle, but that does not imply that such objects "don't experience time". Others have brought up the argument that ds^2 = 0 for a massless particle, but that does not imply that such an object doesn't "experience time". Photons, in particular, have properties that change while they move, namely, the orientation of their polarization vector. Photons can also acquire an effective mass while travelling through matter. Virtual photons don't necessarily move at the speed of light. There are many obstacles in the way of making the poetic sounding claim that massless particles "don't experience time". I would beg of this community to provide us all with a link to an article describing an experiment that demonstrates that massless particles "don't experience time". Until someone provides that evidence, it is completely correct to assume that all particle/field properties are functions of space and time, and thus "experience time" in one way or another. Cougar2013 (talk) 20:42, 27 January 2015 (UTC)