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I'd appreciate it if people knowledgeable in statistical mechanics could take a look at this article, which is up for AfD. I hope the issues with it are obvious. -- The Anome (talk) 16:22, 1 January 2009 (UTC)

Relativistic heat conduction?

Nanog (talk · contribs) just wrote a new article, Relativistic heat conduction. Take a look at it. JRSpriggs (talk) 00:56, 2 January 2009 (UTC)

Could someone expert in QFT take a look at that article? It is written so poorly that it can only be understood by someone who already knows the stuff being "explained". -- Army1987 – Deeds, not words. 18:17, 2 January 2009 (UTC)

Interesting - I thought I did know the spin-statistics theorem very well, but the mathematical context in which I know it*) is not even hinted at in the article, and on the other hand I've never seen the arguments given there (and find them confusing or misleading at places). So, yes, for me it seems that a complete rewrite is warranted - but wouldn't that rather lead to some disagreement with the previous authors? --B. Wolterding (talk) 21:01, 2 January 2009 (UTC)
*) Streater/Wightman, "PCT, Spin and Statistics, and All That" (Benjamin, 1968)
If the proof given is really due to Schwinger, then I'm sure it's correct, or at any rate could be made correct. But it's not explicitly cited, so it's hard to check. It's certainly not the most common proof, but it seems potentially shorter and more transparent than the most common proof. It might make sense to put in the more common proof, but leave the current one in as well--after citing and clarifying it. --Steve (talk) 22:38, 4 January 2009 (UTC)

Odd template

What do you think of the template below?

I've fixed the most blatantly wrong things with it (adding italics and links, etc.), but I consider it somewhat misleading:

  • It seems to imply that gravitation is not part of classical mechanics;
  • A theory of quantum gravity worthy of the name would be relativistic (I guess that quantizing gravity in Galilean space and time would be much less funny, and much less useful), and hence it would include c; the actual difference between QG and TOE is not that the latter uses the speed of light, it is that the latter would describe electromagnetism, strong interactions, and weak interactions, too.
  • I think that one could probably find many "Other (c, G, ħ) subjects" other than Planck units and Hawking radiation (even though I can't think of one right now).

Do you think this template can still be useful for anything, provided it's fixed, or shall I take it to TfD? -- Army1987 – Deeds, not words. 17:09, 4 January 2009 (UTC)

I'd say it's best deleted. Second best would be to link only to things (like string theory) that are actually theories of everything, maybe plus standard model and either quantum gravity or general relativity as the background components. We already have templates for {{Beyond the Standard Model}} and {{Theories of gravitation}}. :-) --Steve (talk) 23:20, 4 January 2009 (UTC)

Inconsistency in titles such as kilometre, milliampere, etc.

Please see Wikipedia talk:WikiProject Physics/Article titles about multiples and submultiples of units. -- Army1987 – Deeds, not words. 17:53, 4 January 2009 (UTC)

Centrifugal Force

The situation at centrifugal force is still in a bit of a mess. We have a special article called 'Reactive Centrifugal Force' which caters for this subject. But the term 'reactive' is a misnomer. In a circular motion caused by tension in a string, the string causes the inward centripetal force. But it is the outward centrifugal force that causes the tension in the string in the first place. The centrifugal force is pro-active. It is not reactive.

There is more about centrifugal force in another article entitled 'Centrifugal Force (rotating frames of reference)'. In co-rotating situations we have centrifugal force.

These two articles need to be joined together into one, and grossly simplified.

We need a simple introduction. "Centrifugal force is the outward force that arises in connection with rotation". We then need a few simple examples including Keplerian orbits and the centrifuge. David Tombe (talk) 06:04, 5 January 2009 (UTC)

x[t]

In several articles (Hamiltonian mechanics#Relativistic charged particle in an electromagnetic field, Lagrangian, and some other ones which I can't remember), I've seen square brackets used to denote function arguments. I think that they look quite weird, and when nested they can become awkward to read (e.g.

,

it's hard to read with all the vertical lines which are part of the brackets, would look much better with round parentheses, at least for the innermost ones:

.)

It is just me? -- Army1987 – Deeds, not words. 16:14, 6 January 2009 (UTC)


Well it is often done the distinguish a functional as in the following case from Lagrangian,
.
In such a case it can be quite useful. However, this does not seem the case in the examples you quote. Those might just be a severe case of mathematica'rites (mathematica puts function arguments in square brackets). (TimothyRias (talk) 16:33, 6 January 2009 (UTC))

Does this topic deserve its own article? Wouldn't it make more sense to merge it into Energy? -- Army1987 – Deeds, not words. 17:27, 6 January 2009 (UTC)

Hi there,

I started a discussion here about articles related to capacitance. At the moment, we have several very long articles with huge scope, which all overlap significantly. I think we need to decide on a better way to divide up the subject matter, which may involve some page moves. Please join the discussion! Papa November (talk) 15:03, 11 January 2009 (UTC)

Discuss here. JocK (talk) 04:12, 12 January 2009 (UTC)

The article ARPES has been listed again as a copyright concern (earlier today I removed the duplication I saw, but evidently multiple sources are involved). Presuming that the IP contributor who tagged it is correct, the article was clean at this point. There's been a lot of work since then, and I am by no means in my field. Is there anyone at the project who would be willing to help clean this text by revising problematic material rather than its being simply gutted? (It's tagged "low" importance, fwiw.) --Moonriddengirl (talk) 20:18, 13 January 2009 (UTC)

I found quite a few sentences that were copied verbatim from those publications. I reverted to an old revision that does not contain any copyright infringements. Ruslik (talk) 09:15, 15 January 2009 (UTC)
Thank you for your assistance. I'll mark this one resolved at the copyright problems board. --Moonriddengirl (talk) 11:49, 15 January 2009 (UTC)

This article has been proposed as a featured article. It is listed under the Physics WikiProject, so please take a look and comment here. Thank you.—RJH (talk) 23:00, 14 January 2009 (UTC)

Uhs (167) - Ust (173)

See Wikipedia:Articles for deletion/Unhexseptium. Elements 167 to 173 have been sent for deletion as pure speculation. Note that even the chemical properties cannot be predicted, since some theories say that no electrons can be added to the electron shells beyond 139. 76.66.198.171 (talk) 00:50, 16 January 2009 (UTC)

Quality assessment done!

As of 13:11, 16 January 2009 (UTC) all 11,962 articles in this project have a quality rating. Well done everybody. There are however still 4,548 articles awaiting an importance assessment. (TimothyRias (talk) 13:11, 16 January 2009 (UTC))

Very nice. I'm sorry I haven't much in the last weeks, but good to know others were at work. Thanks to all who helped.Headbomb {ταλκκοντριβςWP Physics} 19:38, 16 January 2009 (UTC)

Featured article nomination

The article on vector spaces is up for featured article nomination. Please opine here. Jakob.scholbach (talk) 16:00, 17 January 2009 (UTC)

Italicizing the symbol for the "gee" unit?

Please take a look at Talk:G-force#Italicizing and subsequent sections of that page. -- Army1987 – Deeds, not words. 17:17, 17 January 2009 (UTC)

Vital article replacement

I have proposed the replacing of Kinetics (physics) with Newton's laws of motion on the Vital Article list. My reasoning is on that talk page, but basically boils down to Kinetics being a little-used term anymore, and being an article designated "Low" importance. Comments would be greatly appreciated.-RunningOnBrains 16:52, 20 January 2009 (UTC)

The merger proposal at Talk:Emission spectrum has received little comment, especially from people who would be likely to perform any significant changes. –OrangeDog (talkedits) 17:50, 20 January 2009 (UTC)

Hydrino theory → Blacklight Power, Inc.

Hydrino theory is up for renaming again... 76.66.198.171 (talk) 04:24, 21 January 2009 (UTC)

verification of edit in g-force

Could somebody verify my use of a source at: [1], it's being claimed that I'm misrepresenting the source, but I don't believe that to be the case.

There's a copy of the important part of the source at: [2].

Many thinks.- (User) Wolfkeeper (Talk) 09:11, 21 January 2009 (UTC)

You are correct. JRSpriggs (talk) 09:37, 21 January 2009 (UTC)
Many thanks!- (User) Wolfkeeper (Talk) 10:57, 21 January 2009 (UTC)

Forwarded from OlEnglish's talk page, new contributor seeking help.

I have written a rather absurd interpretation of quantum mechanics http://wiki.riteme.site/wiki/User:Fx303#Vector_Energy_Interpretation_of_Quantum_Mechanics which, however, is based on solid math and science references. The purpose of this interpretation is not a serious attempt to explain QM, rather to provide a means for alternate views to be expressed through semantic games over "real" and "imaginary" numbers and when to toss the imaginary component. This is for the purpose of helping someone see it in a new light and come up with a real explanation.

The VEIQM would run like: The missing atoms are not missing. They converted to negative vector energy photons and went to the universe's bank of energy-time uncertainty from which other parts of the universe can borrow. Somewhere, a bunch of atoms were needed, so that void borrowed from uncertain energy-time and brought them into existence there (wherever there is). To conserve stuff, whatever was needed took place (like creating a neutrino - hah) and all laws were satisfied. As silly as it sounds, maybe someone finds a new line of inquiry and actually figures it out from reading this.

I propose the idea to you as last editor of that article, the above is my contribution and explanation of intent.

Your call what to do with it, as a newcomer I would request to defer to you on this issue. Fx303 (talk) 14:13, 21 January 2009 (UTC)

Welcome, and thanks for contributing! I was the last editor of that article however I only did a minor formatting edit of the layout to conform to Wikipedia's Manual of Style and I have no knowledge or expertise on the subject. I forwarded this message to Bosenova's Talk page and to WikiProject Physics' Talk page where I'm sure someone can help you with this. Sounds like it could be viewed by some editors as violating Wikipedia's Original Research policy however you mentioned it was based on "solid math and science references" so just be sure to cite your references, and go ahead and be bold! I'll help with any copy editing or formatting you may need. Expanding stubs is in my opinion the most productive way to contribute to Wikipedia so I'm grateful we have knowledgeable editors such as yourself that can do that. OlEnglish (talk) 22:05, 21 January 2009 (UTC)

CP-violation

It has been proposed below that CP-violation be renamed and moved to CP violation. Though the vote counting listed at WP:RM is false, because consensus can change thus the "votes" from 2007 and 2008 don't really count. 76.66.198.171 (talk) 14:57, 22 January 2009 (UTC)

I don't quite get what you're trying to do by dismissing the 2007/2008 "votes". Everyone's agreeing that CP-violation should be unhyphenized.Headbomb {ταλκκοντριβςWP Physics} 19:56, 22 January 2009 (UTC)
They're old, so people might have changed their minds, which means that they don't usually count towards the determination of consensus, even if it is commonsense. It would have made more sense to close the old discussion and start a new section. The consensus can change has been used several times at WP:RM to exclude excessively old opinions from the current discussion, other than in reference to the older discussions. 76.66.198.171 (talk) 04:36, 23 January 2009 (UTC)
Besides, the hyphen makes no gramatical sense. it really shouldn'y be there. Dauto (talk) 03:01, 24 January 2009 (UTC)

This article is edit protected for some unfathomable reason... 76.66.198.171 (talk) 08:21, 25 January 2009 (UTC)

Can dimensionful quantities be fundamental?

Please take a look at Talk:Planck units#Need to revise 'Planck units and invariant scaling of nature'. -- Army1987 – Deeds, not words. 13:03, 25 January 2009 (UTC)

Clearup of classical mechanics

RunningOnBrains's posting about replacing Kinetics (physics) in the list of vital articles reminded me that I had noticed a while ago that the whole area of classical mechanics could do with being sorted out.

The classical mechanics article describes mechanics as being divided into three branches: Statics, "Kinetics", and Kinematics. Modern texts typically combine Kinetics and Kinematics and call it Dynamics, or don't differentiate between any of the three branches, just using the term classical mechanics for the whole subject. (More on this division is here.)

Then, looking at what articles exist in this area, there are:

  • Classical mechanics - overview article (B class).
  • Statics - OK as far as it goes (start class).
  • Analytical dynamics - pretty poor article, mainly concerned with defining dynamics (which it does inconsistently), and doesn't have any physics content. Doesn't ever explain why it's got "Analytical" in its title.
  • Kinematics - fairly good article (B class).
  • Kinetics (physics) - mainly points out that "dynamics" is the modern term in a mechanics context, also uses of "kinetics" such as reaction kinetics, growth kinetics, etc.
  • Dynamics (physics) - link to Analytical dynamics, brief discussion of dynamics as the time evolution of physical processes
  • (There are also disambiguation pages at Kinetics and Dynamics.)

So, I'm posting here to try to establish whether there's a consensus on how the area of classical mechanics should be divided up on Wikipedia? (Perhaps something that matches a standard division of the topic as currently taught?) Is it best presented as all one subject, two subjects, or three? Under what titles?

(Just to be clear, I'm not proposing that any of these articles should be deleted - even if it's felt that some terms are no longer used, the articles should probably explain their former use and point out the current terminology.)

Thanks! Djr32 (talk) 14:31, 25 January 2009 (UTC)

Throughout wikipedia, various particles are given various names. For example, for example pion and pi meson are the same particle, positron and antielectron are the same thin, tau particle, tauon and tau lepton are the same particle, etc... So how about naming them all consitently?

  • IMO, mesons and baryons should all follow the "[Symbol] meson" and "[Symbol] baryon" (meaning pi meson and k meson over pion and kaon), etc...
  • The antiparticles should be named "anti[particle name]" aka positron would be renamed antielectron, positive muon (if it exists) would be renamed antimuon, etc...
  • Charged leptons should be electron muon and tauon (rather than tau lepton), for uniformity reasons.
  • Individual neutral leptons should be electronic neutrino, muonic neutrino and tauonic neutrino rather than electron neutrino, muon neutrino, tauon neutrino.
  • The various articles on wikipedia should follow these conventions (or whatever is agreed upon in the end) by default.

What say you? The only real problem I foresee with this is converting positron to antielectron, but doing the conversion would IMO improve the understanding of non-expert readers.Headbomb {ταλκκοντριβςWP Physics} 01:47, 25 January 2009 (UTC)

I'd prefer the article for each particle to be at the name the particle is most commonly referred to by; it's true that muon vs tau lepton sounds inconsistent, but such is the English language, and it's not Wikipedia's job to fix that. But anyway, as long as each name in use for a particle redirects to the right article, I have no strong opinion about that. -- Army1987 – Deeds, not words. 02:06, 25 January 2009 (UTC)
IMO, this is a bad idea. First of all it conflicts with the wikipedia'S NPOV. The wiki should report the terminology as it used, not as some editors think it should be used. It has been the long standing habit that when there exist different conventions that the editors of the article in question decide which one to use. (see citation conventions, english vs. american spelling, etc.)
Moreover some of the choices you are making are very unconventional and would actually produce more confusion because the wikipedia convention is very different from that used in the real world. Especially, the use of antielectron instead of positron would be weird since in some cases it has always been refered to as positron. But also your convention for the neutrinos is far from usual. (TimothyRias (talk) 11:02, 25 January 2009 (UTC))
Well the details can be argued on, but what I mean is have some kind of universality on Wikipedia. If someone reads tau lepton, then tau particle, then tauon, then one can easily get confused. If electron neutrino is found more often than electronic neutrino, then have all the neutrinos be refered to (by default) as electron/muon/tauon neutrino. What's above is a first draft. The "by default" in there means that when a topic hasn't strongly rely on a particular use of say "positron", then antielectron would be used, unless of course people agree that on that page, positron is prefered to antielectron for XYZ reason. For example, positron emission tomography would obviously still use "positron", but a random article such as the article on antimatter would use antielectron. Unless, of course, people agree one that article's talk page that "positron" is more appropriate than antielectron for that article. Headbomb {ταλκκοντριβςWP Physics} 15:18, 25 January 2009 (UTC)
I think it might be OK to write up a general guideline for a default usage of terms, but only if there is a quite general consensus on this within WP physics. It might be helpful for editors trying to find out what terminology to use in an article. However, suggest a guideline should be very explicit that it is just a suggestion. In the end the choice of terminology should be with editors of a particular article, and last thing I want is to be stuck people arguing with me because to such an so guideline said so. (We have enough of those as it is, note WP:BURO)
That being said I think the default usage should the usage that is most general in the rest of the world. It is IMO more important that we reach so consistency with the rest of the literature. Instead of some internal consistency between the naming of essentially different things. I would suggest (based on my own perception and some simple google counting):
  • leptons: electron, muon, and tau (lepton). (searching for 'tau AND electron' yields a 100 times more hits on google than 'tauon AND electron' (the AND electron was added to ensure uasage in the right context))
  • tauon vs. "tau lepton" yields 777,000 vs 75,500 hits for me, while tauon +electron vs. +"tau lepton" +electron yields 10,400 vs 37,500. I don't know how you got that 100 times difference. Did you put tau lepton in quotes? (And yes google hits fights limitations and all that jazz applies). Headbomb {ταλκκοντριβςWP Physics} 05:38, 27 January 2009 (UTC)
  • Pion and Kaon over Pi-meson and K-meson. Google hits on these are somewhat evenly distributed (large depending of the search context),but I believe that the terms Pion and Kaon are much more likely to be known to 'lay' readers, with Pi-meson and K-meson being (relatively) more common in technical usage.
  • neutrinos: (electron) neutrino, muon neutrino and tau neutrino. These are two orders of magnitude more common on google than the -ic version proposed before. Note that exact flavour isn't that relevant it is usual better to just say neutrino, because due to high mixing of flavours the different flavours can't really be considered distinct particles.
  • Welcome to the 21st century ;). Look up PMNS matrix and neutrino oscillation. Not only do neutrinos mix, but two of the three mixing angles are near maximal. So although particle physics interactions will produce pure weak eigenstates, these are actually superpositions of the (physical!) mass eigenstates. Moreover, the lightest neutrino cannot really be by any right assigned to one of the weak generations. Hence there are many situations where it is just better to talk about neutrinos instead of talking about a specific flavour. (ie. nuclear reactors produce high amounts of neutrinos, etc.) However, there still will be situations in which the flavour is unambiguous and relevant. (ie. a W- boson can decay in a tau and tau neutrino.(TimothyRias (talk) 09:21, 27 January 2009 (UTC))
  • I'm aware of all of that. But the fact remain that people want and do talk about individual neutrino flavours, and that any discussion of the conservation of lepton numbers and weak decays will involve specific neutrino flavours. And the fact that some detectors are sensitive to only some flavours of neutrinos rather all of them means that there's something meaningfull about the concept of neutrino flavours.Headbomb {ταλκκοντριβςWP Physics} 10:14, 27 January 2009 (UTC)
  • The antiparticle issue is clear (anti(particlename)) with the exception of the positron vs antielectron issue. 'antielectron' is much more common than I had thought. So I guess it is open for debate. I would tend to let the context decide what to use.
I'm of course well aware of the limitations of google as a measure, but it does give some indication of its usage. (TimothyRias (talk) 10:12, 26 January 2009 (UTC))

Radio active → Radioactive decay

This redirect has been nominated for discussion on WP:RfD 76.66.198.171 (talk) 06:57, 27 January 2009 (UTC)

I've nominated Casimir cones for deletion. Although I am 99.4% sure that it is a hoax, please take a look at it in case I'm wrong. -- Army1987 – Deeds, not words. 17:42, 27 January 2009 (UTC)

Does the Introduction to special relativity need massive reorganization?

See Talk:Introduction to special relativity#A radical reorganization of this could be useful. -- Army1987 – Deeds, not words. 22:52, 27 January 2009 (UTC)

Periodic table (extended)

Periodic table (extended) has been nominated for deletion. 76.66.198.171 (talk) 04:29, 28 January 2009 (UTC)

The 2Z-N correlations at AfD

Wikipedia:Articles for deletion/The 2Z-N correlations. A very short article with many references, mostly by one author, concerning relations between the stability of nuclei and their numbers of protons and neutrons. —David Eppstein (talk) 16:45, 29 January 2009 (UTC)

Plasma propulsion engine & Ion thruster

Plasma propulsion engine and Ion thruster seem to be about the same topic... perhaps a merge is in order? 76.66.196.229 (talk) 07:33, 30 January 2009 (UTC)

They are not quite the same I think; an ion thruster is essentially a low-energy, high-current particle accelerator (ie, non-thermal), while I believe a plasma propulsion engine typically uses EM means (eg, arcs, RF,...?) to heat a thermal plasma that may be magnetically guided or isolated from cold solid structure. Wwheaton (talk) 19:14, 30 January 2009 (UTC)
The way they are currently written, they cover the same material. If we use the recent SciAm article for sequestration, the ion thruster article needs to be drastrically reduced in scope, since it covers everything right now. 76.66.196.229 (talk) 06:43, 31 January 2009 (UTC)
I am about to do two things re. this issue:
  • 1) change the merge tags so they both point to Plasma propulsion engine (now they point to the two different articles separately), and
  • 2) Advocate that the articles be kept separate, with the boundary being as I suggested above, that ion-drives be defined as high-current, low-energy particle accelerators that use non-thermal electric field means to accelerate their ion reaction mass, and "Plasma propulsion engines" be defined as devices which heat a plasma to high temperature by some means and then typically use magnetic fields to keep the hot plasma from destroying the engine structure, and to form a nozzle so that the random thermal velocity of the plasma is converted into a unidirectional exhaust. I believe this is the common understanding in the field, though I am not really an expert in this area and could be mistaken (if so, I invite others to correct me.)
If the logical boundary is accepted, it will mean merging the (recently added, I think) material on thermal electric drives into the plasma propulsion engine article, and removing the duplicate material from the ion drive article. Wwheaton (talk) 07:38, 31 January 2009 (UTC)

Image in dire need of modification

See Wikipedia:Help desk#Image in dire need of modification Nil Einne (talk) 12:19, 17 January 2009 (UTC)

I think any color coding for this image would be misleading and cannot see any way to color it better, since the horizontal axis is wavelength, and each corresponds to a color. Better just to make all the curves black, I think. But sorry, I do not know how to do this myself. Wwheaton (talk) 20:22, 31 January 2009 (UTC)

A grain of truth in Biophoton?

I opened a RFC on the Biophoton article. Is it all pseudoscience or is there something worth keeping? Also see Talk:Biophoton. 129.177.30.18 (talk) 10:33, 29 January 2009 (UTC)

It makes no difference to a photon whether its source is a living being or not, or whether its sink is a living being or not. It obeys Maxwell's equations in any case. JRSpriggs (talk) 22:07, 29 January 2009 (UTC)
I don't think a photon ever obeys Maxwell's equations, since it belongs to the limit of QED opposite of the wave limit. ;) Anyway, as far I can discover the article is not claiming that there is anything special about the photons themselves, but rather that (active) biological tissue emits photons with anomalously high energies compared to the blackbody spectrum. It goes further into the possible source of these photons and various claims about the role they play in the metabolism of cells, which (according to the article) are mostly discredited by research. For its claims it is quoting articles from respectable articles. I can't say how accurate it representing these quotes, but I see little reason to believe that the article is very much off. That being said, the article is clearly of start level and could use some work is somebody actually cares. (I don't) (TimothyRias (talk) 09:04, 30 January 2009 (UTC))
But Maxwell's equations do apply to QED (provided you interpret them the right way, that is)... :-) --A. di M. (talk) 00:41, 31 January 2009 (UTC)
Like Tim I don't really have a problem with the article (other than it's general "startness"). Looks accurate and all. As long as this is about photons involved in biological processes, and not "biophoton" in the sense of "homegrown, biologial, not photons produced in evil corporate chemical plants, healthy, etc..." this is perfectly legit. Adding something about biophotons being normal regular photons would go a long way for the read IMO. Headbomb {ταλκκοντριβςWP Physics} 20:12, 31 January 2009 (UTC)