Wikipedia talk:WikiProject Physics

WikiProject Physics
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Physics world article

Hi all, wikiproject physics was mentioned in a recent physics world article, if you are a member of the Institute of Physics then you can read the article here: http://physicsworld.com/cws/article/indepth/47019 (actually even if you aren't a member I think you may still be able to register and read the article anyway. There is an associated blog here: http://physicsworld.com/blog/2011/09/become_a_wikipedian.html . It's nice to know that the general physics community are now talking about Physics articles on wikipedia. Polyamorph (talk) 14:54, 16 September 2011 (UTC)

A little bit overenthusiastic, isn't it? I don't think Wikipedia is that awesome. In particular, I'm surprised they chose Introduction to special relativity as an example: it's one of the worst “Introduction to” articles, IMO. (I set out to improve it a few years ago, but I never got around to come up with anything decent.)
― A. di M.​_plé​^dréachtaí 10:26, 18 September 2011 (UTC)

I don't think it's overenthusiastic. The IOP is all about promoting physics so their articles on public outreach tend to be enthusiastic, but this is a good thing IMO. Perhaps they could have consulted wikiproject physics before writing the article for a better choice of articles, but then again it's better to have an outside perspective, since most wikipedia users are not involved with editing. Polyamorph (talk) 10:50, 18 September 2011 (UTC)

Literature of phase boundaries

Literature of phase boundaries is a new article. The format---including getting the software to number the references, if that is appropriate in this case---could use some work by someone skilled in Wikipedia's conventions for this sort of thing.

Are there particular lists that should link to this?

And which articles should link to this? The links still need to be put there. Michael Hardy (talk) 16:05, 20 September 2011 (UTC)

Nice to have literature to refer to, however, I don't think it warrants it's own article. Would be better to transfer the content to talk or userspace and use the references to help improve existing articles. Polyamorph (talk) 11:31, 24 September 2011 (UTC)

Really crazy stuff possibly going on

What do you think of this? My first thought was that there must have been some kind of glitch, but according to rumours people have known about this anomaly and tried to explain it for several years. (Also, they're changing the schedule of the first day of the national congress of the Italian Physical Society next Monday, in order to fit in it a one-hour talk about that.) Do you think it would be premature to mention that in WP articles (e.g. Unsolved problems in physics)? (As for me, I can't wait for the talk on Monday to hear what people think might be going on. A part of me believes/hopes that there must be some not-so-crazy explanation for that.)
― A. di M.​_plé​^dréachtaí 19:10, 23 September 2011 (UTC)

It already has brief mention in the neutrino article. Until it's confirmed independently, to this level of precision, by other labs, that's sufficient mention IMO. According to the press release yesterday, the FTL measurement is expected to be the result of systematic errors rather than actual FTL travel, but they're having trouble pinning down what the systematic error is (obvious possibilities were ruled out). --Christopher Thomas (talk) 20:51, 23 September 2011 (UTC)

On this topic, could the project members keep an eye open for well meaning but completely unbalanced additions by runby editors going of the media hype? TR 22:15, 23 September 2011 (UTC)

I already had to remove a paragraph in Special relativity on it.

Most likely it is a mistake of some kind. Otherwise, neutrinos would be tachyons which would allow an effect to precede its cause. A failure of SR would be far less likely than either of those, IMHO. JRSpriggs (talk) 06:34, 24 September 2011 (UTC)

It probably is an error, however it is being reported by the mainstream press and other reliable sources. Although it clearly doesn't warrant article re-writes, it does deserve a mention. Polyamorph (talk) 07:05, 24 September 2011 (UTC)

I can see why you removed the arxiv reference, however the BBC references only goes to show how notable the "discovery" is. I think the paragraph was well sourced, not sure if it belongs in special relativity but it is sufficiently notable and sufficient sources had been given in that case. If not then there are numerous other sources that could be provided instead including e.g. nature news http://www.nature.com/news/2011/110922/full/news.2011.554.html . I agree we should be careful though to make sure the claim is discussed according to WP:DUE. Polyamorph (talk) 07:12, 24 September 2011 (UTC)

Oh sorry I didn't see Christopher Thomas's comment that it is already mentioned in the neutrino article. I agree that this is sufficient mention so it's right to remove it from special relativity. Cheers, Polyamorph (talk) 07:14, 24 September 2011 (UTC)

Tachyon neutrinos (while retaining Lorentz invariance) wouldn't behave like that: less energetic neutrinos such as those in SN1987A would have to travel even faster, but those travelled within a few parts per billion of c. (Unless antineutrinos have different m² than neutrinos or stuff like that, which I would regard as somewhat less crazy than Lorentz violations.) Still, such a collaboration looking for systematic errors for years and failing to find an error one order of magnitude larger that the sum in quadrature of all the errors they did find is also somewhat crazy. Someone in the internet suspects a software bug, but in my experience data with that kind of errors often look quite ‘unnatural’ and these data don't to me. Right now my money would be 10% on Lorentz violation, 40% on crazy proprieties of neutrinos, and 50% on experimental errors (25% of which on stuff like someone deliberately messing up with the GPS system–the US military used to officially do that, but in such a way I think we would have detected, so if this is the answer they must be doing it in a more subtle way.)
― A. di M.​_plé​^dréachtaí 11:26, 24 September 2011 (UTC)

FWIW, I have requested semi-protection of Speed of light and Neutrino. DVdm (talk) 09:18, 24 September 2011 (UTC)

Mass–energy equivalence is also receiving some attention from well meaning anon and newly created accounts. Polyamorph (talk) 09:29, 24 September 2011 (UTC)

If you read the article, you'll see that measuring the time of flight is a tour de force. Unlike the distance measurements, what they had to do here is not yet routine to the accuracy necessary for this experiment. With clocks at different locations being involved, they had to account for many more factors than in case of measurements involving only one clock. All sorts of delays when signals travel through the electronic equipments now don't cancel anymore. Also simply reading off the time of events in CERN from the clock there that is synchronized using the same GPS signals as used to synchronize the LNGS clock is already quite difficult. They did perform a direct measurement to compare both clocks to each other via a third device that was physically transported from CERN to LNGS to check if this is done correctly, but this was a one off measurement. Count Iblis (talk) 16:32, 24 September 2011 (UTC)

Those delays when signals travel through the electronic equipments were each measured several times with three different methods which agreed with each other, and, if I understood today's talk (which was streamed from Gran Sasso to L'Aquila through a very poor internet connection, with a very loud mains hum, and the speaker was speaking English with such a strong Italian accent I started to wonder if he was doing that on purpose) correctly, the physically transported clock thing was done as an extra precaution after they were already quite confident of the synchronization, which turned out to be about 2.4 ns off.
― A. di M.​_plé​^dréachtaí 19:39, 26 September 2011 (UTC)

Michelson–Gale–Pearson experiment

See Wikipedia:Peer review/Michelson–Gale–Pearson experiment/archive1.

Discussion consolidated at the above link. Headbomb {talk / contribs / physics / books} 15:29, 25 September 2011 (UTC)

Dark matter and black holes (again)

An editor has recently inserted mention of primordial black holes as a dark-matter candidate into Dark matter (edit | talk | history | protect | delete | links | watch | logs | views). I seem to recall a lengthy discussion of that topic from a few months ago, with the removal or substantial downsizing of mention of that claim, but I'm having trouble finding the threads in question (might have been at one of the black hole / primordial black hole / micro black hole / black hole with a side of fries articles, or the MACHO article, or elsewhere). If anyone else feels up to vetting the addition, by all means do so, as my understanding was that microlensing experiments had ruled out most forms of such claim and failed to provide actual evidence for any form of that. ObCaveat: I am not an astronomer or astrophysicist. --Christopher Thomas (talk) 20:03, 26 September 2011 (UTC)

Found at least one of the threads: Talk:Dark matter#Lack of evidence for WIMPs. --Christopher Thomas (talk) 18:11, 29 September 2011 (UTC)

Magnetically Inflated Cables

described here from the StarTram concept www.niac.usra.edu/files/studies/final_report/1133Powell.pdf Is it a new idea, does it deserve an article ? Since i do not have the capability to understand the science behind the paper, can someone be nice and point me in the right direction for vulgarization ? --Beaucouplusneutre (talk) 21:21, 26 September 2011 (UTC)

The StarTram article sounds like a sales pitch for this particular group's magnetic launch scheme. I've tagged it as such, so that someone with time on their hands can tone it down a bit.

With regards to the magnetically inflated cables redlink, the concept is fine, but I don't think it'll pass the notability guideline for its own article (that would require more than one person or research group to be writing about it). The core concept is the same as the one they propose to use for lifting the end of the gen-2 magnetic launcher: run current through a superconducting loop of wire, and magnetic forces will push outwards on the loop (making it fully expand into a ring shape if it wasn't already expanded). What the cable paper is proposing is to build large kevlar balloons in any desired shape (along the same lines as inflatable space habitat proposals), but to "inflate" them by running current through wire loops embedded within them instead of by filling them with gas.

I hope this gives you enough context to help! --Christopher Thomas (talk) 00:01, 27 September 2011 (UTC)

Planck length article template locks in eroneous value

article value correct, box value wrong. Talk page had this noted 12 March 2010 but not fixed as yet. Might need template write access to fix.

See CODATA2010 to verify,

http://physics.nist.gov/cuu/Constants/Table/allascii.txt

Planck length 1.616 199 e-35 0.000 097 e-35 m — Preceding unsigned comment added by 69.234.106.21 (talk) 04:08, 28 September 2011 (UTC)

Images from arxiv papers

Hi there,

Just a quick question, are images within a pre-print paper in ArXiv considered as released into the public domain? A couple of images from the OPERA neutrino paper have found their way in the CERN Neutrinos to Gran Sasso article and I am unsure of the correct attribution. Regards ^Khukri 05:57, 29 September 2011 (UTC)

No. The copyright of images of articles on Arxiv are property of their authors (or in some cases their employer). So, unless the images have been explicitly released to the public domain, they are not free to use.TR 06:02, 29 September 2011 (UTC)

Cheers ^Khukri 06:46, 29 September 2011 (UTC)

Article assessment

As of yesterday ALL articles in the WikiProject Physics have both quality and importance assessments! Special thanks to user:meno25 for his tireless activity in assessing the last 1000 or so stubs! TR 05:59, 29 September 2011 (UTC)

List of important publications in geology up for deletion

List of important publications in geology has been nominated for deletion, with the implicit argument that such a list is original research; the discussion is at Wikipedia:Articles for deletion/List of important publications in geology.  --Lambiam 21:12, 1 October 2011 (UTC)

This follows deletion of List of important publications in biology at AfD. Several others are also listed at AfD. --Bduke (Discussion) 22:49, 1 October 2011 (UTC)

Red Link Recovery Live

Howdy. For a while now, the Red Link Recovery Project has been using a tool (named Red Link Recovery Live) to find and correct unnecessarily red links in Wikipedia articles. For example, for the red link Annual Reviews of Nuclear and Particle Science on the article Leptogenesis (physics) it might suggest that the link be changed to Annual Review of Nuclear and Particle Science.

The tool currently has around 1100 suggestions for corrections to red links on articles relevant to this project (those in Category:Physics_articles_by_quality). Each time you visit this link, you'll be shown two or three of these suggested fixes. I'll be delighted if anyone with a few minutes to spare would care to do so and help improve the quality of this project's articles. - TB (talk) 14:37, 3 October 2011 (UTC)

Einstein vs Poincare spilling into Speed of light

About POV-pushing at Wikipedia:Neutral point of view/Noticeboard#Priority for the concept of the constant speed of light (leftover from this talk page section). DVdm (talk) 16:48, 3 October 2011 (UTC)

It all has to do with some creationist twit saying that Einstein's Theory of Relativity promoted moral relativism. Amazing what rubbish people pushing things like that will get up to. Dmcq (talk) 17:06, 3 October 2011 (UTC)

Single purpose account blocked for sockpuppetry, as was to be expected. DVdm (talk) 21:12, 3 October 2011 (UTC)

Virtual particle article contradicts uncertainty principle article

The article on virtual particles contradicts the article on the uncertainty principle by stating:

"The virtual particle forms of massless particles, such as photons, do have mass (which may be either positive or negative) and are said to be off mass shell. They are allowed to have mass (which consists of "borrowed energy") because they exist for only a temporary time, which in turn gives them a limited "range". This is in accordance with the uncertainty principle which allows existence of such particles of borrowed energy, so long as their energy, multiplied by the time they exist, is a fraction of Planck's constant."

while the article on the uncertainty principle states:

"Another common misconception is that the energy-time uncertainty principle says that the conservation of energy can be temporarily violated – energy can be "borrowed" from the Universe as long as it is "returned" within a short amount of time.[26] Although this agrees with the spirit of relativistic quantum mechanics, it is based on the false axiom that the energy of the Universe is an exactly known parameter at all times. More accurately, when events transpire at shorter time intervals, there is a greater uncertainty in the energy of these events. Therefore it is not that the conservation of energy is violated when quantum field theory uses temporary electron-positron pairs in its calculations, but that the energy of quantum systems is not known with enough precision to limit their behavior to a single, simple history. Thus the influence of all histories must be incorporated into quantum calculations, including those with much greater or much less energy than the mean of the measured/calculated energy distribution." --130.225.244.206 (talk) 18:17, 4 October 2011 (UTC)

Although these paragraphs are not expressed very clearly, I do not think that they actually contradict each other. Energy is exactly conserved. However, the division of energy between a system which endures for a limited time and the rest of the universe is not well-defined. The shorter the duration, the more vaguely the energy is known. For virtual particles, the relativistic energy-momentum equation fails to provide an exact relationship between the mass and the energy and momentum of the particle. That is because it is actually an artifact of destructive interference of the wave function with itself. JRSpriggs (talk) 00:24, 5 October 2011 (UTC)

Two accelerating universe articles

Could someone look at reconciling / merging the old article accelerating universe with the recently created accelerating expansion of the cosmos? Though recently created (mainly by just two editors), the second article is actually longer. However it also suffers from formatting and style problems. Now that the accelerating universe has won the Nobel prize, people are going to be looking for this information and it would be nice have things be cleaned up and merged as appropriate. Dragons flight (talk) 19:02, 4 October 2011 (UTC)

AfD of Neo-relativity

New article Neo-relativity has been sent to AfD here as OR. JRSpriggs (talk) 08:13, 6 October 2011 (UTC)

This is the work of Gameseeker (talk · contribs). A second article of theirs, Rajagopal Kamath, is also being reviewed at AfD. It might be worth vetting their recent contributions to Neutrino, Fifth force, Theory of relativity, Special relativity, and Speed of light, just in case they've been on a linking spree. --Christopher Thomas (talk) 08:55, 6 October 2011 (UTC)

OPERA neutrino anomaly

We should have a look at the OPERA neutrino anomaly article. --D.H (talk) 16:29, 9 October 2011 (UTC)

It seems a nice article. It's not pushing a POV and is well sourced. The experiment is certainly notable owing to the huge media attention it received. Even if/when the results are proven wrong (as is quite likely) the experiment itself will remain notable. But I agree that the article and related article should be watched to make sure dubious information isn't added. Polyamorph (talk) 17:49, 9 October 2011 (UTC)

Some news stories mentioned that they even corrected for the rotation of the Earth. This makes me wonder whether the error might lie in how that correction or another correction was done. Thus it would be nice to see the article list the various corrections and say something about how they were done. JRSpriggs (talk) 06:26, 10 October 2011 (UTC)

That's a well-enough-known source of error that I'd expect it to have been very carefully corrected for. I'd wait until one of the many groups mulling over the results puts out a critique paper before adding commentary about sources of error (beyond just listing ones that have been noted by the media). About all that can be reliably/verifiably said right now (as far as I know) is that they checked (list of things) and have presented their work for others to check. --Christopher Thomas (talk) 07:31, 10 October 2011 (UTC)

Yes, but I saw a textbook on special relativity once which had an error in one of the solutions to its problems. Even supposed experts can make a conceptual mistake by implicitly assuming pre-relativistic ideas. If they assumed that going once around the Earth would return them to the original reference frame, then they would be making such a mistake. JRSpriggs (talk) 11:14, 10 October 2011 (UTC)

Why do you feel it would be more likely for them to have made an elementary mistake than a mistake with one of the other error sources that's more difficult to analyze or more difficult to account for systematic errors with?

Even disregarding that question, why do you feel it's the job of the Wikipedia article to go down the list of possible errors and say, "this is what it could likely be", rather than wait for external research groups studying the problem to do that?

It's possible that I'm misunderstanding what your position is, but I really don't see why the Wikipedia article about the experiment has to contain very much at all about this before people have published critiques of the experiment in appropriate journals. --Christopher Thomas (talk) 19:31, 10 October 2011 (UTC)

The simple answer is that our opinion on the accuracy of the experiment and the possible sources of error is irrelevant. You are absolutely correct in that until such critiques are published in reliable sources we should not be adding our own opinions on the matter per WP:OR. Polyamorph (talk) 19:37, 10 October 2011 (UTC)

Though obviously not something one puts in Wikipedia, I would mention that I actually calculated the size of the motion of the Earth corrections shortly after the paper came out and concluded that they were significantly smaller than the reported effect. Dragons flight (talk) 19:48, 10 October 2011 (UTC)

Yes, you need much higher speeds. You can also quite easily calculate that to get the synchronization wrong by 60 ns, you could synchronize the clocks in a frame that is moving at about twice the velocity the GPS satellites. Obviously, they didn't synchronize the clocks in this way, but hypothetically, you can imagine that you synchronize clocks in the frame of a GPS satellite and then, instead of subtracting a 30 ns time difference to correct for this, you add 30 ns due to some software bug, leading to a 60 ns error :) . Count Iblis (talk) 20:09, 10 October 2011 (UTC)

Indeed, a software bug is the most plausible-sounding (to me) of the proposed explanations of the anomaly I've heard. (Neglected GR effects? FFS, Earth's r_{Schwarzschild}/r is a hell of a lot smaller than 2.45×10⁻⁵.) ― A. di M.​_plé​^dréachtaí 17:23, 11 October 2011 (UTC)

Superfluid vacuum

A new article has shown up: Superfluid vacuum (edit | talk | history | protect | delete | links | watch | logs | views). Quite a few redirect pages point here (the most-linked ones being Superfluid vacuum theory (edit | talk | history | protect | delete | links | watch | logs | views) and Logarithmic BEC vacuum (edit | talk | history | protect | delete | links | watch | logs | views)), with a very large number of articles containing links to one of the many redirect pages.

My first impression due to the minimal history at the primary article and the large number of redirects/aliases is that this is someone's pet model and that one or more editors have gone on linking sprees pushing it. That said, I am not an expert in the field. Anyone else care to take a look and comment? I encourage using the "what links here" tab, as the web of linking is rather extensive. My concern is violation of WP:UNDUE. --Christopher Thomas (talk) 10:25, 10 October 2011 (UTC)

Breaking down maintenance categories in terms of project importance

Does anybody know, if there is a way to get break down of the various maintenance attention categories in terms of the project importance? For example, producing a list of all top importance physics articles that are tagged for requiring additional references, or all low importance physics articles tagged for notability concerns. Ideally, I would like to create a table like Wikipedia:WikiProject_Physics/Current_status_of_physics_articles, but instead of the quality ratings having various maintenance categories. This would be a very useful tool in monitoring the project article quality, and gives us a handle on reducing maintenance backlogs based on the priorities of our project. Any idea if this is possible and how?TR 14:59, 10 October 2011 (UTC)

White hole article

The White Hole article seems very poor and unscientific to me in a couple of passages. There is no mentioning of the problem of white holes existing at all but rather sci-fi like speculations about parallel universes... Can someone have a look at it? --Schiefesfragezeichen (talk) 21:52, 11 October 2011 (UTC)

I gave up watching it a long time ago. It needs a near-complete rewrite by someone very familiar with the textbook treatments of it. (Direct links: White hole (edit | talk | history | protect | delete | links | watch | logs | views)) --Christopher Thomas (talk) 23:01, 11 October 2011 (UTC)

Well, the content currently IS very close to standard textbook treatments of the subject. The text has many issues, which need to be dealt with. Like the use of URLs in mid text. But the scientific accuracy is actually pretty good.TR 06:13, 12 October 2011 (UTC)

Perhaps a cleanup occurred in the meantime, then. When I un-watched it, it had suffered from a series of substantial amendments that weren't consistent with each other, and a large and disorganized "in popular culture" section. It's been a while, though. --Christopher Thomas (talk) 07:38, 12 October 2011 (UTC)

It still needs a lot of clean up, but has been mostly fairly accurate for a while now (more than a year). It is not a very good article at the moment, but at least it is not flat out wrong.TR 08:17, 12 October 2011 (UTC)

Gravitomagnetism

I believe someone we have had some dealings with before is editing Gravitomagnetism. Anyone like to look at it and confirm my suspicions and delete the lot/tell me I'm paranoid as the case my be. Thanks Dmcq (talk) 16:06, 12 October 2011 (UTC)

He seems to have rediscovered the centrality of the Earth in the cosmos. The caption of a new illustration says "By the end of the continuum's gravitational life cycle, its gravitoelectromagnetic matter waves become spaghettified into a "dendritic drainage system", collecting the continuum's gravitoelectric force (wavefunction, information[7][8]) to a single point—the planet Earth. Thus, the informational progress of mankind is the final crescendo of the continuum's gravitational evolution.". JRSpriggs (talk) 17:38, 12 October 2011 (UTC)

Please, delete the whole mess. Another contribution from this IP to Free entropy has been undone. I really like the article on Gravitomagnetism, and this pasta thing is clearly nonsense. --Daniel (talk) 19:21, 12 October 2011 (UTC)

Can someone fix the archive? It's located at Talk:Gravitomagnetism/archive1, but should be located at Talk:Gravitomagnetism/archive 1 . 70.49.126.190 (talk) 04:04, 13 October 2011 (UTC)