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Draft:Prism_Spectrometer in AfC[edit]

Hi WP:PHYS,

The AfC queue is really (read, completely) backlogged - I'd like to invite any of you to poke this as well as any other physics related draft in AfC. Cheers! Accents 06:04, 15 June 2015 (UTC)

Also Draft:Extended Interaction Oscillator, Draft:Gamma voltaic cells and Draft:Precession Electron Diffraction. Thank you, FoCuSandLeArN (talk) 14:18, 19 June 2015 (UTC)

If the project can set up a way to prominently display

Draft Physics articles

perhaps in the "to-do" list, these drafts might get more expert reviews sooner rather than later. Roger (Dodger67) (talk) 16:44, 22 June 2015 (UTC)

There would also need to be a to-do list to tag drafts with the WPPHYSICS banner in the first place for it to appear in that category. (For instance, Draft talk:Extended Interaction Oscillator does not contain a WPPHYSICS banner) ; (Perhaps by looking through the WPCOSMOLOGY and WPASTRONOMY drafts to see which are also physics topics) -- 70.51.203.69 (talk) 04:58, 25 June 2015 (UTC)
AFC is in the process of instituting a workflow update that includes adding project banners to all drafts, so expect the tagging rate to increase soon. Of course anyone is welcome to add project banners to drafts. Roger (Dodger67) (talk) 21:09, 26 June 2015 (UTC)
So, are we agreed, that WPPHYSICS should tag draft articles? (If so I'll spend a few minutes going through drafts and adding banners) -- 70.51.203.69 (talk) 05:13, 27 June 2015 (UTC)

Velocity-addition formula and Thomas precession suggestion[edit]

Velocity addition in relativity is, in the usual presentation in a textbook something quite easy. It is captured in essence by the formulae ("standard configuration")

v_x = \frac{v_x' + V}{1 + \frac{V}{c^2}v_x'},
\quad v_y = \frac{\sqrt{1-\frac{V^2}{c^2}}v_y'}{1 + \frac{V}{c^2}v_x'}, 
\quad v_z = \frac{\sqrt{1-\frac{V^2}{c^2}}v_z'}{1 + \frac{V}{c^2}v_x'}

and, when confined to a plane,

v = \frac{\sqrt{v'^2 +V^2+2Vv'\cos \theta' - (\frac{Vv'\sin\theta'}{c})^2}}{1 + \frac{V}{c^2}v'\cos \theta'}, \quad
\tan \theta = \frac{\sqrt{1-\frac{V^2}{c^2}}v'\sin \theta'}{v'\cos \theta' + V}.

Derivations are two- or three-liners.

Velocity addition in relativity is, when taken to the full extent, as mathematically involved as you wish. Goldstein:

  • "The decomposition process [describing successive pure Lorentz transformations as a pure Lorentz transformation preceded, or followed, by a space rotation] can be carried through on the product of two pure Lorentz transformations to obtain explicitly the rotation of the coordinate axes resulting from the two successive boosts [that is, the Thomas rotation]. In general, the algebra involved is quite forbidding, more than enough, usually, to discourage any actual demonstration of the rotation matrix"

Physically, it has implications that made people (non-cranks) see paradoxes (Macanu paradox). I believe the situation was not fully resolved until 1990.

Now we have these two articles where Velocity-addition formula actually treats a little advanced stuff truly belonging elsewhere, while (imo) failing to treat the simple stuff (not all formulae there, complicated proof) adequately, which should include the formulae (all of them), full easy proofs and applications, e.g. aberration of light. Thomas precession is entirely nontechnical today.

I suggest we collect the advanced stuff somewhere, perhaps Thomas precession, perhaps a new article Thomas rotation, which would make sense because Thomas precession really is a physical phenomenon with mathematical root Thomas rotation. Lorentz transformation would make sense too, but I don't know whether people want to allow for that article to swell much more. Meanwhile, Velocity-addition formula should be reduced to the basics as given in textbooks. YohanN7 (talk) 14:50, 5 July 2015 (UTC)

Agreed. For supporting the "advanced stuff" in the Thomas precession article, along with Goldstein's classical mechanics and Jackson's classical electrodynamics (both in their second editions), Barut's book Electrodynamics and Classical Theory of Particles and Fields (uses classical methods) and Ryder's QFT (uses Lorentz group theory) could be good sources. Landau and Lifshitz volumes 2, 3, or 4 possibly may have something on the Thomas precession. Need to check these later. M∧Ŝc2ħεИτlk 10:18, 6 July 2015 (UTC)
Nothing in L&L. References will become a problem. The full results on Thomas rotation are fairly new and aren't present in any of the classics. The best references I could find are original research papers, the A. A. Ungar papers from 1988-89. Some of these are referenced in Velocity-addition formula. They are good, but there may still be problems because Ungar took these results and developed a completely new theory by abstraction, see Gyrovector space, an article I just discovered we have, see also my comment at Talk:Gyrovector space. So far nothing is wrong, it is perfectly natural. What seems strange is that it appears as a one-man show. Moreover, Ungar wrote a book on his new theory and the first few chapters can be found online (search his name and go to his university homepage):
  • ...
  • Chapter 3: The Einstein Gyrovector Space
  • ...
  • Chapter 5: The Ungar Gyrovector space
  • ...
See the problem?
I'd like to see a reference to Ungar's 1988-89 results (we don't need the gyrovector stuff) from a third party. I personally think the results are legitimate, they look credible and they should easily be verifiable numerically, but full proofs aren't published (due to their complicated nature, I believe that actually, referring to Goldstein). YohanN7 (talk) 11:01, 6 July 2015 (UTC)
Of course there's something in L&L. The hyperbolic velocity space of Ungar figures in a problem (with solution) on p. 38. A bit brief for referencing though. This is further referenced in a modern paper as "perhaps the most intriguing approach", search for Relativistic velocity space, Wigner rotation, and Thomas precession (link was blocked). Ungar's book is mentioned in passing. YohanN7 (talk) 11:51, 6 July 2015 (UTC)
I'll copy this discussion to Talk:Thomas precession, and we can continue there. YohanN7 (talk) 12:13, 6 July 2015 (UTC)

Opinion needed[edit]

Draft:Lifshitz Theory of Van der Waals Force is up for review. I believe Lifshitz's contributions are duly stated in van der Waals force. Would there be any need to have a separate article? I wouldn't think so, as they can always expand the latter one. Any comments are appreciated. Cheers, FoCuSandLeArN (talk) 20:23, 12 July 2015 (UTC)

I would like to see it kept. It is more focused and goes into more detail than the other article. Xxanthippe (talk) 22:26, 12 July 2015 (UTC).

Edits at Nicolas Léonard Sadi Carnot[edit]

Someone contacted me about reviewing ongoing dubious edits at Nicolas Léonard Sadi Carnot, (diff of the relevant edits). Looks suspicious to me, but the changes are fairly technical, and other than going through and tagging with a bunch of CNs, I don't think I'll be much help at the moment. Anyone with a bit of time and some understanding of Thermodynamics want to take a crack at this? Previous discussion on Vsmith's talk page and my talk page. 0x0077BE (talk · contrib) 12:41, 13 July 2015 (UTC)

Requested move for hexaquarkdibaryon.[edit]

For some reason this isn't picked up by AAlerts, so I figured I'd give a notice here. You can join the discussion at Talk:Hexaquark. Headbomb {talk / contribs / physics / books} 14:20, 17 July 2015 (UTC)

Draft:Quantum thermodynamics[edit]

Hello WP:PHYS,

A network of over 200 experts in the field of quantum thermodynamics (the European Commission-funded COST Action MP1209 "Thermodynamics in the Quantum Regime") has been working hard to overturn the judgement handed down on the "quantum thermodynamics" article submitted several months ago. It appears now that the situation has stagnated, with the advice on the draft page being that it is the specialist editors here who can overturn that decision. To add insult to injury, the current article is one sentence long: "Quantum thermodynamics is the application of quantum information theory to thermodynamics." Whilst this is more accurate than the redirect to the article on quantum statistical mechanics that was in operation some time ago, this is an insult to those of us who took the time out to pen an article that is in their field of specialisation (for information's sake: Prof Ronnie Kosloff and his group), only to be told that the matter is already covered elsewhere when it most definitely is not. I would understand the behaviour of the editors if there was some scientific motivation for their actions, but there is none: There is full consensus in the field for what "quantum thermodynamics" refers to, and it is not the same as "quantum statistical mechanics".

Could you please advise on the best way forward? Andre Xuereb (talk) 14:34, 27 July 2015 (UTC)

Andre Xuereb, the main concern, from what I can tell, is that the draft might not meet the concerns listed in the deletion discussion. Granted, that discussion happened in 2012, but I think that it is still a valid point to make. If I get time in the next day or two, I will compare the AfD, the draft, and the rather lengthy discussion the last time this page was brought before WP:PHYS and see if a solution/compromise/what have you can be attained.
As a note, I can understand your frustration, but keep in mind the majority of AfC reviewers do not have degrees in Physics and would not be able to give a proper review (hence the request to allow WP:PHYS/reviewers like me a chance to review it properly). This has been on my to-do list for a while, but unfortunately it's been a low priority due to me moving recently (and then I forgot). Primefac (talk) 14:43, 27 July 2015 (UTC)
Hello Primefac. Thank you for your time; please do not confuse our frustration with lack of appreciation! I would just like to comment that the deletion discussion you refer to seems to be for a different article, since the draft I refer to was first submitted in March 2015. Interestingly, it seems that the redirect was lifted some time this month or last month. Andre Xuereb (talk) 15:00, 27 July 2015 (UTC)
Not to split hairs (since obviously there's a three year difference), but looking at the pre-AfD page it's the same subject. The result of an AfD applies to the subject as a whole, not the writing in the article itself, which is why it's necessary to compare those concerns with the new draft. I believe that someone recently saw the draft and thought that the result of the AfD was no longer valid (there is no "block" on someone going against an AfD discussion, and unless someone notices that an editor has slipped it in there, some changes can last for years). Primefac (talk) 15:15, 27 July 2015 (UTC)
Primefac: Understood, but I wish that whoever takes this case up notes the following points: (i) The 2012 article does not include much in the way of mainstream content, whereas the 2015 version significantly improves this, and indeed include many peer-reviewed references from a multiplicity of groups; (ii) the current situation is that Wikipedia seems to accept that "quantum thermodynamics" is distinct from "quantum statistical mechanics," because the article is now a stand-alone one, albeit a stub, but the editors are refusing that the content from the draft, which is largely a summary of peer-reviewed content taken from what is accepted in the field as "quantum thermodynamics" literature (too many sources to list, but I would take it that most physicists are familiar with Physical Review Letters, Physical Review A, Nature Physics, New Journal of Physics, etc., and their high standards), fashioned into a coherent article, replaces this stub; (iii) no one is in any way advocating that the article is not in need of editing. In particular, point (ii) changed quite recently and seems to me to have shifted the discussion away from the subject and towards the content of the draft. Andre Xuereb (talk) 13:51, 28 July 2015 (UTC)
Yes check.svg Done. Primefac (talk) 12:31, 31 July 2015 (UTC)

AfC submission 28/07[edit]

See Draft:Weyl semimetal. Thank you, FoCuSandLeArN (talk) 18:56, 28 July 2015 (UTC)

It seems like a nice article, certainly well-referenced and has nice diagrams (the first diagram could have clearer labeling for the "Fermi arc", but its not a big deal). No expert on the topic, but it could be launched into mainspace for physicists to edit. M∧Ŝc2ħεИτlk 21:40, 31 July 2015 (UTC)
This draft has been accepted. Primefac (talk) 21:50, 31 July 2015 (UTC)

Lagrangian[edit]

Anyone interested in Lagrangian mechanics and field theory may want to see this, since it will affect a number of articles. M∧Ŝc2ħεИτlk 21:45, 31 July 2015 (UTC)

Rainbow Gravity theory / "Path of Balance Project"[edit]

Would someone familiar with the subject matter please take a look at this edit to Rainbow Gravity theory and determine whether it is appropriate? Thanks. TJRC (talk) 19:54, 3 August 2015 (UTC)