Wikipedia talk:WikiProject Physics/Archive August 2011
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Xi-sub-b
Are any changes to List of baryons (question also posted there) called for because of the observation of a new particle, the neutral Xi-sub-b (Ξb0)? See http://www.sciencedaily.com/releases/2011/07/110720162045.htm -- Jo3sampl (talk) 16:21, 2 August 2011 (UTC)
- It's in the list as the first "bottom Xi" entry, marked as not yet observed. At minimum, it'd be changed to "observed", and a reference to the paper (not the press release) added. Xi baryon contains more data for it from a 2006 reference, but it's flagged as uncertain. --Christopher Thomas (talk) 16:54, 2 August 2011 (UTC)
Treatments of the magnetic dipole field
Much the same treatment of the field of a magnetic dipole can be found in Dipole#Field of a static magnetic dipole, Magnetic moment#Magnetic dipoles, Magnetic dipole–dipole interaction, and Force between magnets. The most specific, Magnetic dipole–dipole interaction, is also the most sketchy. The redirect for Magnetic dipole goes to Magnetic moment#Magnetic dipoles. Conspicuously missing from this list is Magnetic field, whose disambiguation line says it is "about a mathematical description of the magnetic influence of an electric current or magnetic material."
Where should the material on magnetic dipoles go? Is it really useful to have a Dipole page that is explicitly about magnetic and electric dipoles? Why not follow the approach of most encyclopedias and have Magnetic dipole and Electric dipole (the latter instead of Electric dipole moment), while Dipole is just a disambiguation page? Any general mathematical statements about dipoles could be in Multipole expansion.
- Hmm, not sure what to make of this. IMHO, at the very least Electric dipole moment and magnetic moment (aka magnetic dipole moment) should stay as separate articles. These are important physical quantities that depending on the situation may or may not have anything to do with actually dipoles. (For example there is a whole industry of trying to measure the electron's EDM as a precision test of the standard model).
- I'm not sure there even exists a non colloquial use of the term "a dipole" (electric, magnetic, or otherwise). I guess there sort of is. Although colloquially you can call any object with a non-zero EDM an "electric dipole", that term more specifically refers to a system of two opposing charges, etc. I guess it might be a good idea yo have Magnetic dipole and Electric dipole as articles describing these specific configurations. Dipole should probably be a dab page.TR 11:14, 3 August 2011 (UTC)
- I agree that dipole should be a disambiguation. Right now it parrots a grab-bag of different articles (electric dipole, magnetic dipole, dipole antenna, ...) and it would be better to just link to those different articles instead. I also agree that renaming electric dipole moment to electric dipole (with slightly broader scope) and likewise magnetic dipole moment to magnetic dipole would be an improvement. Multipole expansion would benefit a lot from a few examples of monopoles, dipoles, quadrupoles, etc., in different fields, especially with diagrams. For example, the dipole article says what a flow dipole is, which is better than nothing...but the multipole expansion article could say what a flow monopole is AND what a flow dipole is, which would make everything clearer. I can't think of any example where you would want to say what a Dipole XYZ is without also saying what a Monopole/Quadrupole XYZ is.--Steve (talk) 14:11, 3 August 2011 (UTC)
- I strongly object to renaming electric dipole moment to electric dipole, etc. Electric dipole moment and magnetic dipole moment are important physical quantities that deserve their own articles. The are important in many fields ranging from chemistry to elementary particle physics. The articles on these quantities should explain why these quantities are important and what they signify. Renaming the articles to "electric dipole" would shift the subject to a much more muddled subject of examples of dipoles. Moreover, in an article called "electric dipole", there would be no room to talk about the role of electric/magnetic dipole moments in elementary particle physics. (Nobody in his right mind would refer to the electron as an electric dipole, even though the standard model predicts that it has an non-zero electric dipole moment)TR 20:21, 3 August 2011 (UTC)
- If Electric dipole moment is not renamed, there should probably be a separate article entitled Electric dipole for sections like Dipole#Electric dipoles that don't fit comfortably within the subject of electric dipole moment. RockMagnetist (talk)
So far there seems to be consensus that there should be a separate article called Magnetic dipole, containing material like that in Magnetic moment#Magnetic dipoles, while the rest of Magnetic moment stands in for Magnetic dipole moment as well. What about Magnetic dipole–dipole interaction - any reason to keep that as a separate article? RockMagnetist (talk) 22:20, 3 August 2011 (UTC)
- I think it makes sense that if/when the article Magnetic dipole is created that Magnetic dipole–dipole interaction would naturally get absorbed into that article. The section on Magnetic Dipoles in Magnetic moment already contains the subsection Magnetic moment#Forces between two magnetic dipoles which could be merged with the potential energy description in Magnetic dipole–dipole interaction, while Magnetic dipole–dipole interaction#Dipolar coupling and NMR spectroscopy could be part of an examples section. Punk physicist 19:30, 5 August 2011 (UTC)
Multipole
That leads to the question: How to improve multipole expansion and multipole moments and spherical multipole moments and axial multipole moments and cylindrical multipole moments, especially to incorporate physical intuitive examples... --Steve (talk) 14:11, 3 August 2011 (UTC)
- If you're planning to rewrite the n-pole moments and multipole expansion articles, it's probably a good idea to at least make WP:WPMATH aware of this thread (and consult them further if desired), to avoid stepping on toes. I'm not sure which side of the fence physicists are on, but I know that engineers and mathematicians have exactly opposite ways of explaining things (engineers start from concrete examples and special cases and work towards the general case, mathematicians start from the general case and work down towards specific special cases and introduce examples at the end). So, no matter how the articles end up structured, there will be vigorous debate about how best to do it. --Christopher Thomas (talk) 17:09, 3 August 2011 (UTC)
- I thought it might be wise to make this a separate discussion section, since it introduces several new pages. RockMagnetist (talk) 18:31, 3 August 2011 (UTC)
- After thinking about it more, I now think it would be better to write some separate articles: Multipole expansion (electrostatics); Multipole expansion (magnetostatics); Multipole expansion (electromagnetic radiation); Multipole expansion (acoustics). Each article would at least contain pictures of canonical monopole & dipole & quadrupole sources and the fields that they create; and formulas for the moments and the fields in those cases. I don't think these four topics overlap quite enough to put them all into the same article. For example, electromagnetic radiation has formulas for the electric and magnetic fields, while acoustics has just a scalar pressure. Electrostatics and magnetostatics have both fields and potentials, with different decay rates. They all have different applications and common situations and importance. And so on and so on. But of course, all the articles would repeatedly refer to the articles on the general mathematical formalism (multipole expansion, multipole moments, etc.) --Steve (talk) 23:08, 5 August 2011 (UTC)
John David Jackson
The article entitled J.D. Jackson seems to be incorrectly named.
I would think the correct title for this article should be John David Jackson (physicist). He is noted for authoring a widely used, graduate level, textbook on Classical electrodynamics . ISBN 9780471309321. {{cite book}}
: Missing or empty |title=
(help). He does not appear to be known, or referred to as J.D. Jackson Steve Quinn (talk) 04:37, 4 August 2011 (UTC)
- Never mind - I went ahead and did the page move. The redirects to the related disambiguation page are confusing at this time (imho) ---- see: John David Jackson ---- Steve Quinn (talk) 04:49, 4 August 2011 (UTC)
Requested move: Implications/impact of nanotechnology
For those of you who have an interest in nanotechnology, there is a requested move discussion at Talk:Environmental implications of nanotechnology#Requested move as to the proper name of the Implications of nanotechnology series of articles. Any input would be greatly appreciated! Antony–22 (talk⁄contribs) 06:08, 6 August 2011 (UTC)
Gluons
Gluons interact with each other and are to be found in clusters free from any protons or neutrons, the nucleus is thus made of gluons in this clustered independent "isotope". They are attracted to each other, generating both the strong and the ew force, there may be ground to unified them under discrete conditios, somehow a mirror of the ew unification conditions. — Preceding unsigned comment added by 85.240.8.204 (talk) 03:53, 10 August 2011 (UTC)
- You are probably thinking of the "glueball" particle. These don't form clumps larger than individual glueballs, and glueballs are unstable. The original thread was about (asymptotically) free quarks. --Christopher Thomas (talk) 05:21, 10 August 2011 (UTC)
- Would I be correct in thinking that glueballs decay primarily into pions? JRSpriggs (talk) 20:30, 10 August 2011 (UTC)
References for particle nomenclature
Apparently User:Headbomb believes that particle nomenclature does not need references and that the WP:BURDEN should be on those who think it does to disprove the content. I feel that article content should be referenced, hence the name "tauon neutrino" in the tau neutrino article should have some source to back it up, particularly since none of the existing references uses this terminology. However User:Headbomb seems to find this idea offensive and removed the citation needed tag I had placed without inserting a reference, leaving things only to the edit summary. I admit my own conduct in this dispute has not been the best, turns out Wikipedia tends to bring out the worst in me. Can't be bothered with this site any more. Icalanise (talk) 23:09, 5 August 2011 (UTC)
- I gave him a reference to Eric Weisstein's World of Physics [1] and he dismissed it with a "lolbutts, that's from an internet encyclopedist"-type of answer. Nothing will ever satisfy Icalanise, so let's not feed the trolls. Headbomb {talk / contribs / physics / books} 23:16, 5 August 2011 (UTC)
- Sorry but how can that be used as a source when it does not state what the terms refer to? It just states names, you are assuming it is using Tauon Neutrino as an alternative to Tau Neutrino but that can only be original research.
- Either way, since the information has been challenged by another editor you should have cited your source in the article so others can discuss on the talkpage whether this is an appropriate reference. ChiZeroOne (talk) 23:30, 5 August 2011 (UTC)
- What's the point of adding a reference which he doesn't accept as legit, just so he'll revert it? And for something trivial which can be verified with a basic google search? What's next, we'll need a reference to say hydrogen is called hydrogen? Headbomb {talk / contribs / physics / books} 23:43, 5 August 2011 (UTC)
- Because the removal of sourced (even if contentious) content is always likely to draw attention from other users. Fortunately Wikipedia is more than just two editors and no one has a veto so there's always the potential to find other voices who will enforce the chosen concensus. Frankly others are more likely to be on your side if you've at least attempted to justify the content with evidence. Once you've provided the reference it's the other editors problem to show how/if the source is not valid.
- Btw I'm not saying you're wrong, i'm saying you picked a poor source for it. As a physics grad I have to say i've never heard the term Tauon or Tauon Neutrino before so i don't think it is as obvious as you believe it is. That's why citing challenged statements is important. ChiZeroOne (talk) 23:54, 5 August 2011 (UTC)
- I just explained to you why it is a bad source for the statement you intend it to back up. The page you quote does not connect the term Tauon Neutino as an alternative for Tau Neutrino, it just states the words Tauon Neutrino and it is your assumption that the connection exists. So it doesn't actually back up the claim. The site itself may generally be a good source for many things, what you quoted is not a good source for the challenged statement. ChiZeroOne (talk) 00:19, 6 August 2011 (UTC)
- This is a book that not-quite-explicitly says that tauon neutrino is another word for tau neutrino. It explicitly says tauon is another word for tau, and then it uses the phrases "tauon neutrino" and "tau neutrino" on the same page in a way that makes it obvious they are interchangeable. --Steve (talk) 01:18, 6 August 2011 (UTC)
- Now that's a bit better. ChiZeroOne (talk) 03:59, 6 August 2011 (UTC)
- (ec) Just so that I'm clear here, you're seriously proposing that "tauon neutrino" is used to mean something other than "tau neutrino"? I'm afraid Headbomb is correct in objecting to your statements, and you're causing me grave concern as well.
- That said, per the old Talk:Tau (particle) thread, I question any assertion that "tauon" and "tauon neutrino" are more commonly used than "tau" and "tau neutrino". --Christopher Thomas (talk) 01:24, 6 August 2011 (UTC)
- No i'm saying Headbomb was asked for a source that supported the assertion that a tauon neutrino is the same thing as a tau neutrino, and the source he provided doesn't, the assumption it does is an analysis or synthesis i.e original research. It's not my problem if you cannot understand why this is the case, although i'm astounded that people discussing physics cannot comprehend simple logic. Based only on that source it is original research to claim they are one in the same, that does not mean I seriously think they are not related. This is a question of what a source supports, what we believe is irrelevant. This is all rather pointless anyway as i'm sure there are plenty of better sources that can be provided that demonstrate they are the same. ChiZeroOne (talk) 03:59, 6 August 2011 (UTC)
- "Tauon neutrino" is a bit of a 1980's term (tau neutrino is indeed now more common), but a simple google scholar search will show plenty of academic uses (I see 135) of the term "tauon neutrino," especially in astronomy, and it is also clear that they all mean tau neutrino. What the devil else could they mean? [2] What is this argument about? This kind of thing "I've never heard of this, so I'm going to delete it" is what makes Wikipedia painful. Unless you're pretty sure some peice of physics is wrong DON'T MESS WITH IT. If you think the notation could be improved to a more common one, make sure you're right by looking at the literature, and just link to the more common one (and put the alternate in parentheses). SBHarris 01:28, 6 August 2011 (UTC)
- "This particle is called a tau neutrino. This particle is also called a tauon neutrino. Therefore, tau neutrino is a synonym for tauon neutrino." ChiZeroOne, if I understand, you're objecting to using this logic because it violates WP:SYN. Well, hmm, I suppose it does. But it seems to me that this chain of logic is so ridiculously straightforward and unobjectionable that we can let it be :-) --Steve (talk) 05:25, 6 August 2011 (UTC)
- Sorry but your paraphrase is false. That source does not say any particle is also called a tauon neutrino, it just says the term tauon neutrino without any context whatsoever. Can you not see why that is a problem? It is a pretty damn big leap and certainly not unobjectionable, that makes it a bad source for asserting that it is a synonym. As i said there's no point arguing over what is a relatively minor point here and there are likely plenty of sources that can actually back up the claim. I was only making a point about that one source being inadequate. ChiZeroOne (talk) 16:20, 6 August 2011 (UTC)
- It was not as though the assertion was being removed because it was thought unlikely. A citation was asked for and the request for a citation was removed. This is not a the sky is blue thing. It should be substantiated even if it is probably true. The citation needed should not be removed without a citation. Dmcq (talk) 10:22, 6 August 2011 (UTC)
- Exactly. ChiZeroOne (talk) 16:20, 6 August 2011 (UTC)
- Hardly so. He asked for a reference, I gave him one. Then for some weird reason, we're now arguing that tauon neutrinos refer something other than tauon neutrinos. On the physics WikiProject. Has Wikipedia degenerate so low that we now need a reference to say the colour force is also known as the color force? Headbomb {talk / contribs / physics / books} 17:32, 6 August 2011 (UTC)
- Sorry I couldn't just leave Headbomb to misrepresent me, this will hopefully be my last post here. Headbomb, you didn't put the reference in the article did you? You just deleted the tag, leaving the statement unreferenced. You did this multiple times, EACH TIME LEAVING AN UNREFERENCED ARTICLE BEHIND YOU. If you're not going to put the citation in the article then just leave the tag there. And before you bitch and whine about that I would have reverted I'll point out you did it before I had expressed my reservations about Eric Weisstein's World of Physics. Guess you just assumed bad faith from the outset. Lol. Bye! Icalanise (talk) 18:46, 6 August 2011 (UTC)
I may have to write up this whole conversation for WP:LAME. As a testiment that although some things don't need a citation, per WP:V, somebody's always going to demand one anyway. And this is NOT a "the sky is blue" matter, because the sky is sometimes other colors. This is a "mu meson" = "muon" matter, which is always true-by-definition. It's a matter of equivalent terminology, so well-known that those who don't know it, probably shouldn't edit on the topic at all. SBHarris 21:48, 6 August 2011 (UTC)
- The article is for people who aren't know it alls. That's why they read the stuff. Please provide an inline citation from a reliable source before removing the citation needed. Dmcq (talk) 21:52, 6 August 2011 (UTC)
- You're confusing the reading audience with the editors; they are not the same. For the record, I think a poor reference beats no reference some of the time. However, if we had to reference every line in Wikipedia, indeed every word, it would be unreadable. SBHarris 22:11, 6 August 2011 (UTC)
- You can leave the citation needed notice instead of finding one if you like. No ones going to remove the stuff anytime soon just because it isn't cited. It would however be a good idea if someone who was wondering about this was directed to somewhere that said this convention. Removing the citation needed in that circumstance is wrong. Dmcq (talk) 22:53, 6 August 2011 (UTC)
- You're confusing the reading audience with the editors; they are not the same. For the record, I think a poor reference beats no reference some of the time. However, if we had to reference every line in Wikipedia, indeed every word, it would be unreadable. SBHarris 22:11, 6 August 2011 (UTC)
Wow, this conversation is amazing. I think it certainly deserves WP:LAME treatment. --Falcorian (talk) 04:26, 7 August 2011 (UTC)
- That's what I thought too, but I was too polite to point that out. ― A. di M.plédréachtaí 10:41, 7 August 2011 (UTC)
- Just to get back to Earth. Yes, it is a good idea to provide a reference to back up the fact that an alternative term is actually used for a certain concept. (If alone, because some editor may be unfamiliar with that term actually being used.) For this purpose, it is enough to provide a reference that actually uses the term (in this case World of Physics is a fine reference). Ideally, this reference would mention both terms, but in most cases it is a case of "the sky is blue", if two different sources clearly define the same concept but call it differently. (For example, in this case there is no room for any reasonable amount of doubt that the terms "tauon neutrino" and "tau neutrino" refer to the same thing.)TR 14:01, 7 August 2011 (UTC)
- I'll raise this issue on in the ongoing discussions about "Not Truth" on the verifiability page. Some time ago, I also argued that one has to invoke a "reasonable doubt" concept for verifiability, instead of the currently oversimplified criterium for citation from a single source. Basically, a statement included in Wikipedia should be true beyond a reasonable doubt, given the entire content of all reliable sources on the subject. A "citation needed" tag then has to be a reasonable demand given everything that can be found in reliable sources about the subject. This then also puts a burden of studying the subject on the editor who wants to see a citation for a statement. Count Iblis (talk) 15:34, 7 August 2011 (UTC)
- Well I'd certainly like to be able to differentiate better in the citation needed between the options so people don't just remove things because of a citation needed. Normally though if I had stong doubts I'd simply remove the statement rather than stick in citation needed, I'd probably put a bit about it on the talk page if it had been around for some time. Dmcq (talk) 16:35, 7 August 2011 (UTC)
- I'll raise this issue on in the ongoing discussions about "Not Truth" on the verifiability page. Some time ago, I also argued that one has to invoke a "reasonable doubt" concept for verifiability, instead of the currently oversimplified criterium for citation from a single source. Basically, a statement included in Wikipedia should be true beyond a reasonable doubt, given the entire content of all reliable sources on the subject. A "citation needed" tag then has to be a reasonable demand given everything that can be found in reliable sources about the subject. This then also puts a burden of studying the subject on the editor who wants to see a citation for a statement. Count Iblis (talk) 15:34, 7 August 2011 (UTC)
Discussion at Talk:List of important publications in physics
There's an ongoing discussion about what criteria should be used to decide what's "important" in that list. People should probably chip-in. Headbomb {talk / contribs / physics / books} 17:01, 9 August 2011 (UTC)
Fusion question
I'd like to add a small sentence to most of the nuclear fusion articles, but I don't know the answer: why does the D-T mix have a lower fusion barrier than a T-T mix? The articles explain that T has the highest ratio of electromagnetic to strong charge, so if you follow the logic presented, pure-T would be better. If someone can give me a ref for this, I'll do the work of including it in the various articles. Maury Markowitz (talk) 13:00, 12 July 2011 (UTC)
- We generally do not add the same text to a multitude of articles. Just put it in the most appropriate article!
- This is just a guess, but T-T would require emitting two neutrons rather than one neutron as for D-T, since the main product in each case would be helium-4. Breaking the bond to the second neutron would increase the energy-cost of the process. And as a practical matter, tritium is much more expensive than deuterium, so one would not want to use T-T, if D-T would work. JRSpriggs (talk) 13:57, 12 July 2011 (UTC)
- There are a couple of very detailed articles in the "Encyclopedia of Physics" on fusion that are not overly technical for a non physicist, your local library should have a copy Copernicus01 (talk) 12:33, 12 August 2011 (UTC)
Speed of gravity and speed of light
Light gets refracted in certain elements (like water, glass, transparent objects), and therefore photons slow down going at speeds of less than 300,000 km/s . Is gravity unaffected by refraction and opacity? Negativecharge (talk) 15:04, 18 July 2011 (UTC)
- The best place to ask this sort of thing is probably at WP:RD/S, not here. That's what WP:Reference Desk is there for.
- The short answer is, the fundamental force of electromagnetism always propagates at C (the speed of light in vacuum). I'd expect the fundamental force of gravity to do likewise. There might or might not be the vacuum equivalent of a phenomenon that changes the phase velocity or group velocity of gravitational waves (just as refractive index changes the speed at which light waves propagate), but as far as I know not much in the way of this has been seriously proposed. --Christopher Thomas (talk) 01:40, 19 July 2011 (UTC)
- The absolute value of the coupling constant for gravity is much less than for electromagnetism, so refraction and absorption, if they occur, would also be much less.
- However, the sign is also reversed, and I have no idea what that would do to the effects. JRSpriggs (talk) 07:31, 19 July 2011 (UTC)
- I guess such an effect would be so ridiculously small that it'll never get measured within my lifetime. ― A. di M.plédréachtaí 01:11, 24 July 2011 (UTC)
- Gravitational lens — Preceding unsigned comment added by 166.84.1.5 (talk) 14:52, 25 July 2011 (UTC)
- Gravitational lensing does not work by refraction. Refraction - which requires a change in speed of the wave propagating - is what is being discussed here. --Christopher Thomas (talk) 15:33, 25 July 2011 (UTC)
Ha, I can see a good GR problem in here. I have to think about exam problems, and this may be a good one! Count Iblis (talk) 16:54, 25 July 2011 (UTC)
- Yes. If you insist on continuing to use Euclidian coordinates in non-Euclidian space, it LOOKS like the speed of light is slowing, because it's going through more space than you give it "credit" for doing (it also goes effectively slower because a time dilation effect that is th equivalent of Newtonian gravity, is bending its path by an additional mechanism which is exactly as important for light). All this can be considered as equivalent to a sort of GR refractive index, WRT Euclidian space. Working out the value of this "n" in terms of the G potential, would be a nice extra credit question at the end of a test. Hmmm, the whole thing (gravitational field) ends up producing the effect of a double-concave or "dispersive" lens, though. The simplest solutions are for the length of an imaginary pipe that passes through the exact center of the Earth, where no bending is produced, but the light is slowed down WRT the Euclidian diameter. The "excess" radius r the light travels is proportional to the mass enclosed by the sphere of Euclidian radius the light travels along. The effective n = c/v for that path would be 1+ (r/R) or something, where R is the Euclidian radius and r is the excess from GR effects. SBHarris 19:22, 25 July 2011 (UTC)
- There are no Euclidean coordinates in a curved space, but the principle of equivalence allows you, for a given coordinate map, to consider non-zero Levi-Civita connection as a fictitious force. This does not make that space Euclidean, indeed, because of non-constant Riemann metric. I think, the initial question was not about curvature of the space, but the possibility of slowing a gravity wave below the light barrier, i.e. such that the group velocity become time-like instead of being null. This is perfectly possible for electromagnetic waves, although, as Christopher Thomas remarked, the fundamental force of electromagnetism still propagates on the light cone. The vacuum is Lorentz-invariant, but an optically dense continuum is not, this is the cause. This slowdown appears only due to properties of differential equations, no quantum effects, so such things as coupling constants do not matter. Why should it be impossible for gravity, indeed? Incnis Mrsi (talk) 19:49, 25 July 2011 (UTC)
- Essentially, refraction of light is caused by electrons in the medium being shaken by the incoming wave emitting a wave of their own, so that the ‘total’ wave has a different phase than the incoming one. I'm not entirely sure it can happen with gravity (I wouldn't be surprised if the fact that nuclei and electrons have the same mass-to-‘charge’ ratio, unlike in the EM case, makes their effects cancel out), but if it can, I'd expect n − 1 to be roughly of the order of (particle number density)×(gravitational analogue of Bohr radius)3, by dimensional analysis, which for ordinary matter is ridiculously small. ― A. di M.plédréachtaí 23:40, 12 August 2011 (UTC)
- There are no Euclidean coordinates in a curved space, but the principle of equivalence allows you, for a given coordinate map, to consider non-zero Levi-Civita connection as a fictitious force. This does not make that space Euclidean, indeed, because of non-constant Riemann metric. I think, the initial question was not about curvature of the space, but the possibility of slowing a gravity wave below the light barrier, i.e. such that the group velocity become time-like instead of being null. This is perfectly possible for electromagnetic waves, although, as Christopher Thomas remarked, the fundamental force of electromagnetism still propagates on the light cone. The vacuum is Lorentz-invariant, but an optically dense continuum is not, this is the cause. This slowdown appears only due to properties of differential equations, no quantum effects, so such things as coupling constants do not matter. Why should it be impossible for gravity, indeed? Incnis Mrsi (talk) 19:49, 25 July 2011 (UTC)
Need advice on BSC theory of superconductivity
here. Materialscientist (talk) 10:02, 11 August 2011 (UTC)
Minimal coupling
There is a new article Minimal coupling. It needs a lot of work. JRSpriggs (talk) 19:36, 11 August 2011 (UTC)
Twin paradox
Twin paradox (edit | talk | history | protect | delete | links | watch | logs | views) — A new user seems intent on edit warring to add original research as well as a reference to his own never-cited article from the low-level/fringe journal Physics Essays. Some attention is appreciated. Tim Shuba (talk) 15:38, 14 August 2011 (UTC)
RFC on identifiers
There is an RFC on the addition of identifier links to citations by bots. Please comment. Headbomb {talk / contribs / physics / books} 15:51, 15 August 2011 (UTC)
Marie Poise and her war on identifier links
Marie Poise (talk · contribs) Could someone talk some sense into her? She's removing bibcodes, links to OSTI documents, and everything that's not a DOI from physics articles. Headbomb {talk / contribs / physics / books} 18:05, 16 August 2011 (UTC)
- This is part of a larger AN thread here. The core of the dispute is that User:Headbomb feels that bibcode links should be added to references in many articles, and other editors object to them being added to articles outside of the original scope of the bot proposal discussion. Strong feelings have emerged on both sides (several editors object, several editors endorse the bot's activities).
- My own feeling: Headbomb, please consider the possibility that at least some of these objections have merit. I've noticed (with things like the "tau/tauon" discussions) that you tend to pick a position and then defend it to the death. Your success rate with picking positions the community - and your peers - endorse is only about 90%. --Christopher Thomas (talk) 19:44, 16 August 2011 (UTC)
- Actually, that thread has been resolved. Although I disagreed that bibcodes should not be added on say medicine articles, I agreed to restrict the bot to physics & astronomy until the RFC about whether it should add bibcodes to everything it can add them. This dispute is about Marie removing bibcodes, pmids, OSTI links, etc... from articles that already had them for ages. I created this thread without the knowledge Marie would open another AN thread.
- As for Bibcode bot running on physics and astronomy articles, I did solicit opinions from a vast array of people, including WP Physics, WP Solar System, WP Astronomy, WP Astronomical Objects, WP Space, etc.... Combine this with several thousand edits on Physics and Astronomy articles without anyone ever complaining about anything, and I would find it very hard to believe that Physics & Astronomy people are against this and support this. Headbomb {talk / contribs / physics / books} 20:00, 16 August 2011 (UTC)
New article proposed for deletion
Not quite sure how to add this to the project page itself, so including it here: new article Ritz's Equation has been proposed for deletion. No idea whether it's notable or reproduces existing content myself, so thought I'd alert this project. Thanks. --88.104.36.157 (talk) 09:39, 18 August 2011 (UTC)
Problematic cosmology edits
Recently user Styxpaint (talk · contribs) came to my attention, due to apparent edit-warring at Dark matter (edit | talk | history | protect | delete | links | watch | logs | views) where they seemed to be aggressively pushing a particular alternative model for dark matter. They've left that for the time being, but their edits to Journal of Cosmology (edit | talk | history | protect | delete | links | watch | logs | views), Panspermia (edit | talk | history | protect | delete | links | watch | logs | views), and Weakly interacting massive particles (edit | talk | history | protect | delete | links | watch | logs | views) could stand vetting from editors familiar with those topics (and with associated academic literature, if possible). --Christopher Thomas (talk) 00:14, 20 August 2011 (UTC)
This is a new article by Fedosin (talk · contribs), citing work from a Sergei Fedosin. It normally wouldn't have raised too many redflags, but when the citations given are published on vixra... from a guy who edits mostly on weird topics like strong gravity, and known nonsense like Einstein–Cartan–Evans theory, my BS-dar goes off like crazy. Send to AFD? Notable legit stuff, but bad sources? Notable crank stuff? Headbomb {talk / contribs / physics / books} 06:43, 21 August 2011 (UTC)
- My impression is:
- no evidence of notability
- strong indications for a conflict of interest (which is not a reason for deletion, but increases the need for secondary sources)
- inconsistent content (the first paragraph in 'Applications' contradicts the definition of the operator)
- There's a starting controversy about linking this article from other pages. The author himself seems interested in an 'official' decision about the fate of the article.
- It looks like AfD would be a way to settle this. — HHHIPPO 11:55, 21 August 2011 (UTC)
- I agree with the above. At the least respectable sources are needed. Xxanthippe (talk) 12:09, 21 August 2011 (UTC).
- Before seeing this, I just reverted an unnecessary link by him to this article from special relativity#Force in 4D. Also one might question what is the meaning of a (4-dimensional) covariant derivative of a physical quantity only defined on the trajectory of a particle. JRSpriggs (talk) 13:47, 21 August 2011 (UTC)
- I agree with the above. At the least respectable sources are needed. Xxanthippe (talk) 12:09, 21 August 2011 (UTC).
Upon further inspection, the first source (and only non-vixra source) given is a dead link, and the ISBN is invalid... yeah... Headbomb {talk / contribs / physics / books} 14:11, 21 August 2011 (UTC)
Nommed for AfD. --Izno (talk) 14:29, 21 August 2011 (UTC)
Schwarzschild metric (again)
Remember back when there was an argument at Schwarzschild metric (edit | talk | history | protect | delete | links | watch | logs | views) about coordinate systems?
An anon has started that edit war up again. I reverted once; they reverted my revert. I leave this in the hands of the rest of you, as I'm supposed to be trying to enjoy vacation time right now... --Christopher Thomas (talk) 08:15, 11 August 2011 (UTC)
- The dispute appears to be ongoing. I've continued refraining from participating (I'm still partly burned out), but it's worth keeping an eye on. --Christopher Thomas (talk) 09:00, 16 August 2011 (UTC)
- I've removed the crackpot nonsense again, but the anon is very insistent. I might need some back up from other experienced editors.TR 09:04, 26 August 2011 (UTC)
Article on foundation/history of Classical Mechanics
Hello!
I was thinking about an article on the foundations/history of classical mechanics. It would cover the history of interpretations of classical mechanics, philosophical questions in classical mechanics, Mach's elaborate study on the foundations etc. I found two papers which can be used as sources for a primary draft:
- http://springerlink3.metapress.com/content/b0m6258371775000/
- http://www.springerlink.com/content/j42866672t863506/
Any suggestions or criticisms? — Fιηεmαηη (talk) 15:30, 23 August 2011 (UTC)
- History of classical mechanics looks like it could use some help. ;) --Izno (talk) 15:44, 23 August 2011 (UTC)
List of dualities
See list of dualities. Work that could be done includes:
- Expanding the list;
- Organizing the list into subtopics;
- Linking to the list from appropriate other articles.
Michael Hardy (talk) 14:34, 28 August 2011 (UTC)
- Actually, if it's just an alphabetic list of article titles with no annotations whatsoever, I can't even see the point of it. A category:Dualities with subcats category:Dualities in philosophy, category:Dualities in mathematics etc. would be a more appropriate tool to do the same job. ― A. di M.plédréachtaí 12:27, 30 August 2011 (UTC)
- I think that categories are more vulnerable to vandalism than a list article because there is no unified history for which articles are in a category. If an article is removed from a category by a vandal, then you may not be able to detect that fact or find the article to fix it, unless you happen to be watching that particular article. JRSpriggs (talk) 16:26, 30 August 2011 (UTC)
- Come to think of it, perhaps we need a bot to create a history of membership in a specified category. JRSpriggs (talk) 16:29, 30 August 2011 (UTC)
- Or, in an ideal world, a software extension... Though I've come to treat MediaWiki as though it was carved in stone. ― A. di M.plédréachtaí 17:25, 30 August 2011 (UTC)
- Come to think of it, perhaps we need a bot to create a history of membership in a specified category. JRSpriggs (talk) 16:29, 30 August 2011 (UTC)
- I think that categories are more vulnerable to vandalism than a list article because there is no unified history for which articles are in a category. If an article is removed from a category by a vandal, then you may not be able to detect that fact or find the article to fix it, unless you happen to be watching that particular article. JRSpriggs (talk) 16:26, 30 August 2011 (UTC)
Alternatives to Higgs boson?
I read an article in Tuesday's Washington Post suggesting that the Higgs boson may not exist after all. It said that Higgs is running out of places to hide. Do we have an article on possible alternatives to the Higgs mechanism as explanations for the existence of mass? JRSpriggs (talk) 02:07, 31 August 2011 (UTC)
- I guess I should have done a search before I asked you-all. I found Higgsless model. Is there a better article (this one is kind of sparse)? Which of the alternatives looks best to you-all? JRSpriggs (talk) 02:13, 31 August 2011 (UTC)
It will take a long time to rule out the Higgs, what has happened is that a signal they thought they had seen, seems to be less strong than it looked at first. But 3/4 of the Higgs field has been obverved as explained here:
Fact is that the W+, W‾ and the Z boson each carry three spin degrees of freedom, whereas the Yang-Mills field quanta, which describe their interactions correctly in great detail, each carry only two. Those remaining modes come from the Higgs field. What this means is that three quarters of the field of the Higgs have already been found. The fourth is still missing, and if you calculate its properties, it is also clear why it is missing: it is hiding in the form of a particle that is difficult to detect. LHC will have to work for several years before it stands a chance to see the statistical signals of this Higgs particle. What compounds the matter even more is that there may well be several sets of Higgs fields. If there are two, which is eight quarters of the field, we will get five Higgses rather than one. This would be a quite realistic possibility but it would make the detection of each one of them even harder, because they cause more complex statistical signals that are more difficult to predict.
Count Iblis (talk) 02:41, 31 August 2011 (UTC)
My understanding (as a non-expert who sometimes attends physics seminars) is that all of the alternate models are speculative at this point, without enough experimental evidence to support any of them (or to actually rule out the Higgs boson). I've been given the impression that the Higgs or something very much like it is still considered the most plausible explanation for symmetry breaking (just as supersymmetry or something very much like it is strongly implied to exist, even if the default/simplest description of it turns out to be the correct one).
Regarding the alternatives, I don't think any of them can be said to be favoured over the others by experimental evidence. They should, however, be filtered or ranked based on citations from unrelated authors (per WP:UNDUE), as the last time I glanced at it it looked like an indiscriminate collection of every idea anyone's ever proposed. --Christopher Thomas (talk) 03:14, 31 August 2011 (UTC)
It is apparently something like Greenberger–Horne–Zeilinger state (but without N>2 condition required) described according to New York Times and popular books. Your proposals? Incnis Mrsi (talk) 14:39, 31 August 2011 (UTC)
We also have the NOON state. Count Iblis (talk) 15:07, 31 August 2011 (UTC)