Wikipedia talk:WikiProject Physics/Archive July 2009

Article space troll

Working on glass transition, I ran into a strange edit war. Looking deeper into my opponents edit history, I found that User:Logger9 has created a number of pretty long texts, which he pastes almost at random in articles that are unattended by others.

This reveals a fundamental problem of quality control in WP. While usual vandalism is immediately recognised and reverted, while talk space trolls are sooner or later recognised and kept short of food, this user space troll has surprising success. Several editors intervened in his defense; they admitted that they were unable to understand his contributions, and took this as an indication that the material must be very very scientific. Actually, Logger9 decorates his contributions with tons of references (sometimes more than twenty in support of one statement). For me, this is an obvious sign of lacking judgement, but others are deeply impressed.

Right now, Logger9 has abandoned glass transition. Instead, he has pasted his favorite essays into Plastic deformation in solids. Please have a look - you will rapidly see what I am talking about. -- Cheers, Paula Pilcher (talk) 17:36, 2 July 2009 (UTC)

One more point: In the past, some editors have tried to handle the problem by leaving some unattended articles like physics of glass or Phase transformations in solids to Logger9 in order to keep him out of more often read articles like glass and phase transition. I think, this kind of gentleman's agreement is a foul compromise. There are obvious reasons why we should not tolerate private sandboxes in article space. -- Paula Pilcher (talk) 17:51, 2 July 2009 (UTC)

Let me copy just one paragraph from Phase transformations in solids:

"Critical insight into the nature of the heat flow associated with thermal relaxation may be gained by consideration of Frenkel's observation on thermal conductivity that the quantity of heat flowing to a given volume element is used partly to heat it and partly for performing external work. It should be noted that in Debye's theory of the heat motion in a condensed body, the elastic vibrations describing this motion are treated without any a priori reference to the temperature, the latter being introduced merely as a measure of the average intensity of these vibrations. Such a treatment implies a strict validity of the principle of superposition of normal longitudinal and transverse vibrational modes; i.e. a neglect of their deviations from a linear law of force (anharmonicity)."

It is loquacious, partly wrong, off-topic, and as a whole borderline to nonsense. Yet non-scientists who intervene in this debate with opinions based on purely formal criteria defend these contributions, considering them just a little bit too much "technical". It really seems our policies are incapable of preventing this kind of trolling. -- Paula Pilcher (talk) 15:39, 3 July 2009 (UTC)

I agree, it's garbage. Was it sourced? Verifiable? If not, then WP:V is the relevant policy being violated. If it's sourced but badly paraphrased, it can be repaired to agree with the source. Give warning; after enough ignored warning, call it vandalism and report it as such; if that doesn't work, you have to escalate. It's a pain to deal with such guys, I know. See my recent arguments with User:Brews ohare, who seems well intentioned and knowledgeable, but doesn't seem to have any inhibitions against making up partly wrong and mostly unrelated stuff. Dicklyon (talk) 15:46, 3 July 2009 (UTC)

I tried various ways of escalation ... this talk page is my last hope ... if several of you cast the votes in the deletion debate, perhaps there is some hope. -- Paula Pilcher (talk) 15:55, 3 July 2009 (UTC)

Dark matter on hold for GA Sweeps

The Good Article dark matter has been reviewed by me in accordance with the GA Sweeps process. I left concerns on the talk page; if they are not addressed within seven days the article may be de-listed as a Good Article. Thank you, and happy editing! -RunningOnBrains^{(talk page)} 19:17, 3 July 2009 (UTC)

I don't think a one week deadline is reasonable given the large number of points raised. Most of them are requests for citations for statements that are widely accepted. So, it's not that there are a lot of problematic statements in the article. I think that it is reasonable for the problems to be fixed before September.

I'm sure they'll be reasonable, they were the one time I worked on a GA. As long as the points were being addressed. --Falcorian ^(talk) 00:21, 4 July 2009 (UTC)

Has anyone ever received a referee report from the editor saying: "you got 7 days to revise your manuscript, or else it will be rejected"? Count Iblis (talk) 21:12, 3 July 2009 (UTC)

We didn't even get seven days at WP:CHEMS for sodium hydroxide. The whole process is a farce, best thing to do is to ignore it. Physchim62 (talk) 00:47, 4 July 2009 (UTC)

Plastic deformation in solids

You folks might want to take a look at what is going on here. -- logger9 (talk) 05:49, 7 July 2009 (UTC)

Geomagnetic storm → Geomagnetic solar storm

A WP:RM requested move has been filed to rename Geomagnetic storm → Geomagnetic solar storm

70.29.208.69 (talk) 04:07, 9 July 2009 (UTC)

Need more opinions at Wavelength

We've been having an edit war there, and could use some input from others. It's all pretty well explained on the talk page (start with Talk:Wavelength#The_crux_of_the_problem and work backwards if you care). Dicklyon (talk) 18:21, 21 June 2009 (UTC)

It's still going on. Brews has made a special section Talk:Wavelength#Unconventional definitions about definitions that he wants to push for some reason, and keeps putting stuff into the article that's based on these idiosyncratic extrapolations from sources. Two other editors have pushed back on him with me, and nobody has supported him, but I don't know how to get him to stop, or even slow down, his attack on this and related articles. Dicklyon (talk) 17:29, 9 July 2009 (UTC)

We've got a cry-baby here. I'm not pushing anything - just trying to get Dicklyon to actually say what he wants by providing a straw man proposal. Instead he just deletes material without constructive comment. Brews ohare (talk) 19:14, 9 July 2009 (UTC)

I've been very clear about what I want, and am willing to explain it again to anyone who asks, as I explain it twice daily to Brews. Dicklyon (talk) 19:20, 9 July 2009 (UTC)

Edit warring at Wave

Can we have some more opinions at Wave please? See recent talk sections and edits, between me and Brews ohare. Dicklyon (talk) 17:41, 6 July 2009 (UTC)

I don't actually have time to keep up with throttling him; he has expanded Wave from 21 KB to 33 KB in the last few days, and I'm on the road. The expansion wouldn't be a problem if it had a higher proportion of relevant and correct information, but as usual it's full of idiosyncratic interpretations, complexity, bloat, tangents, and stuff duplicated from other articles, including stuff rejected from wavelength due to being wrong and unsourced. Someone else will need to help with this, or I'll just give it up. Dicklyon (talk) 05:29, 9 July 2009 (UTC)

Brews has also inserted a big chunk of bloated material that was irrelvant at Wavelength into the Dispersion relation article, where it's even further off-topic. I'd appreciate any comments on how to deal with this; or if anyone thinks the content is useful there, I'll leave it alone. Dicklyon (talk) 17:22, 9 July 2009 (UTC)

String theory history

Could editors please contribute to the discussion regarding the history section in the string theory article. Thanks. MP ^{(talk•contribs)} 11:09, 9 July 2009 (UTC)

Merge point mass, point charge in point particle

Hi, everybosy. As I've suggested here, I think is better to merge point mass and point charge as section in the general article point particle. I think it's better that, if someone look for point charge for example, before they'll learn about the general idea of point particle in physics. We can make a single good article from three stubs and I can't see any reason not to do so. --CristianCantoro (talk) 13:30, 19 June 2009 (UTC)

Sounds like a good idea. (TimothyRias (talk) 13:46, 19 June 2009 (UTC))

I'd go even further, and try go get some order into subatomic particle, elementary particle, list of particles as well. Particle (physics) redirects to elementary particle, which is a synonym of point particle: however, there are many important particles in physics which are not elementary! Physchim62 (talk) 14:43, 19 June 2009 (UTC)

Point mass and point charge and point particle are "point" as in "infinitely localized", and only exist in classical physics due to the Heisenberg uncertainty principle. An elementary particle is a real-world thing with a spread-out wavefunction, so is not a "point" particle. --Steve (talk) 15:41, 19 June 2009 (UTC)

Well, point masses and point charges existed (in Physical theory) well before the Schrödinger equation and the uncertainty principle. What exactly is your objection to discussing the distinctions in a single article, rather than spreading coverage over many articles, none of which is accurate? Physchim62 (talk) 17:07, 19 June 2009 (UTC)

Point masses and point charge exist in classical physics theory but do not exist in the universe. Elementary particles are real things that exist in the universe. So I don't think point particle and elementary particle should be combined into the same article. Of course, I think the articles should be accurate however they're arranged. :-) --Steve (talk) 18:05, 19 June 2009 (UTC)

You-all might want to consider whether Test particle should also be part of the merger. JRSpriggs (talk) 05:13, 20 June 2009 (UTC)

(<=) I agree with Steve. My two cents: elementary particles are (forgetting for a moment QM and QFT) point particles, but (not all) point particles are elementary particles. They are different models used in rather different ways. Anyway, I think it's a good thing to get some order between articles (but I don't know your situation, since I'm mostly active here. Instead, test particle is the same thing of point particle (I've only heard about test particles when introducing the electromagnetic field or the gravitational field as a synonym for point charge or point mass). --CristianCantoro (talk) 18:53, 20 June 2009 (UTC)

I think the point particle articles should be merged. Ti-30X (talk) 22:08, 22 June 2009 (UTC)

Do not merge test particle and point particle; they are different physical concepts. The defining property of a test particle is that doesn't effect the field configuration it is supposed to be testing. That is it charge and mass are assumed to be negligible. Point masses and point charges are point-like sources for gravitational and electromagnetic fields. (TimothyRias (talk) 17:19, 23 June 2009 (UTC))

I for one did not understand that - it sounded like you were saying that x is not y because x has the same attributes as y. Where did I go wrong? Abtract (talk) 17:29, 23 June 2009 (UTC)

Let's try it again then. Point masses and point charges are typically sources of gravitational en electromagnetic fields. For example you can calculate the gravitational field generated by a system of point masses. Test particles on the other hand are assumed NOT to generate a gravitation (or electromagnetic) field of their own (are at least it is assumed to negligible.), instead they are used as a theoretical tool to explore an existing gravitational (or electromagnetic) field. As an example take the reduced three body problem this describes three masses the first two are very massive and orbit each other according to the solution of the two body problem, while the last one is a test particle that is assumed to be very light compared to the other masses so that its influence on the other orbits can be safely ignored. (TimothyRias (talk) 18:57, 23 June 2009 (UTC))

I can see your point, TimothyRias. Anyway I wonder if it's worth to keep separeted articles only beacause test particles are point(-like) particles that generate negligible (EM, gravitational) fields. IMHO, I believe it's better to merge the articles and make "test particle" a subsection of "point particle". --CristianCantoro (talk) 07:24, 4 July 2009 (UTC)

No you can't calculate the gravitational field of point particles, that is the crux of the conflict between GR and QM. A point particle has an infinite field; and hence the non-linear interaction of gravitons would cause the field to grow without limit at arbitrarily close points to the point mass. However, I take your point that a test particle is not the same as a point particle. —Preceding unsigned comment added by YouRang? (talk • contribs) 21:23, 13 July 2009 (UTC)

Some articles may be in need of a multidisciplinary approach

I have been trying to add some physical context to the meaning of the R-value and have encountered some opposition to this effort. The article is currently undergoing a process of reduction and the point of view is becoming somewhat restrictive. Science is being downgraded. This raises the question of the scope of Wikipedia articles.

One assumes that we are writing for the general public and that Wikipedia is not a trade journal. Often articles are group projects since very few individuals are competent to speak for society as a whole. In this case the R-value has meaning to the professional sector which not everyone in the trade industry is aware of. The R-value can be defined as the ratio of the temperature difference across a conductor and the heat flux through it and is relevant since the purpose of insulation is to reduce heat flow and the associated temperature regulation costs. I personally do not know who introduced the R-value. Joseph Fourier identifies a constant, H, for the problem of conductance through the air in The Analytical Theory of Heat. He distinguishes it from h, the thermal conductivity. This was in 1822 and there is no need to clutter an article with excessive detail. But some science is essential in the understanding of the R-value which is used to rate insulating material.

The article is in need of improvement and greater expertise would help. The discussion at the level of building codes is often minimal and I doubt that there is a code of silence involved here. Building codes originate as professional codes. They are often adopted as is by the legal community. It is the case of a private code being imposed on the public. The problem one encounters is that of transmission losses along a chain. Information is lost. Wikipedia can offset this through the inclusion of material in its articles. People have a right to understand public code. They have a right to know what is in the public domain and a free press is a means to this end.

It might help if more than one group involved with Wikipedia shared responsibility for the content of and setting goals for articles. This would reduce the power of some "czar" to restrict the flow of information. --Jbergquist (talk) 21:15, 12 July 2009 (UTC)

Point Particle Questions

I have some questions regarding point particles (this is for an article on Wikipedia).

• Are the muon and tau lepton considered to be point particles? I know that they have no internal structure, like the electron so, these are elementary particles. But the fact that they decay during the weak interaction, and the size of the tau lepton have me wondering if these are point particles. (There was one other thing, but I can't recall at the moment what it was.)

• What is the momentum of the electron? Is this is a conserved property? I am having a difficult time determining what it is. Ti-30X (talk) 16:46, 4 July 2009 (UTC)

What do you mean by a point particle? That's not a very useful concept in physics. And electron momentum is not conserved; momentum in conserved in closed systems, but it can move between components of the system. It is also uncertain. But if you know the wavenumber, it's proportional to that, with a factor of Planck's constant. Of course, the point particle concept doesn't have the concept of wavenumber, so maybe that's not what you want to know. Dicklyon (talk) 18:13, 4 July 2009 (UTC)

Dicklyon, I am equating point particle with elementary or fundamental particles. It seems there is a well known Nobel laureate in particle physics (Leon Lederman) who stated that the electron was a point particle. It has spin, mass, and charge, but is considered to be without dimension. It is counterintuitive to the human perspective. He wrote that a particle with point mass, point spin, and point charge does create conceptual problems (IMHO a conceptual problem, doesn't seem to be much of a problem). Anyway here is the link in Google Books. If you have time - enter "point particle" in the search box, click on page 142, scroll back to the bottom of page 141, and then read bottom of page 141, and the whole of page 142, you will see what I mean. (If you have time) Let me know what you think. Thanks. Ti-30X (talk) 03:17, 6 July 2009 (UTC)

"Point particles" are a pedagogical tool for teaching classical physics. They're not real things. --Steve (talk) 19:42, 4 July 2009 (UTC)

Asking "what is the momentum of the electron" is somewhat like asking "what is the velocity of the football". A given electron will have a momentum, then it gets bumped, and then it has a new momentum, then it gets bumped again... --Steve (talk) 03:18, 5 July 2009 (UTC)

Steve, your football analogy agrees with what I was thinking. But for some reason I got the idea there was an established momentum involved for the electron. I don't know where this idea came from. Probably from something I mis-read. The fog is clearing - (not about what I misread) - just as Diklyon wrote, above, momentum is conserved in a closed system. Somehow I must have mixed that up with my question. Ti-30X (talk) 03:17, 6 July 2009 (UTC)

According to string theory, there are no point particles, only little strings which are entities with extension in time and limited extension in one spatial direction (they may be open-ended or loops). If point particles existed, they would require infinite strength of interaction (producing other infinities, previously fixed by renormalization when possible) because the probability of two points colliding is zero. JRSpriggs (talk) 19:37, 5 July 2009 (UTC)

JRSpriggs - this is interesting because renormalization is what is used today. And, (probably as everyone here already knows), around the time QED was being developed there were those pesky infinities. As a solution, Feynman and colleagues came up with renormalization. So this aspect of string theory supports that. Ti-30X (talk) 03:17, 6 July 2009 (UTC)

To Ti-30X: What? Perhaps you misunderstood what I was saying. By "previously", I meant in the dark ages before string theory, which unfortunately still continues in most of particle physics. QED et al implicitly assumes that particles are points (and thus not strings). So of course, they got infinities because of the problem which I mentioned (i.e. no collisions between points). So I cannot see how you can say that string theory supports renormalization and such; it does not. JRSpriggs (talk) 19:35, 7 July 2009 (UTC)

JRSpriggs - Sorry. After re-reading what you wrote - I see that I misunderstood what you were saying. You are right I missed the part where you said "previously". OK I got it now. Thanks for pointing out my error. Ti-30X (talk) 19:45, 7 July 2009 (UTC)

The electron, muon, tau, and the other elementary particles described in the Standard Model are indeed treated as "point particles", in that they don't have a "size" beyond that described by their wavelength. Compare this with an atom, which has an electron cloud of well-defined size, or with a proton, which has a size defined by the wavefunctions of the bound quarks within it. --Christopher Thomas (talk) 01:30, 14 July 2009 (UTC)

Thank you very much Christopher. Ti-30X Ti-30X (talk) 02:43, 17 July 2009 (UTC)

Got a question? Don't ask here!

Talk:Black hole has the advisory note "Got a question? Don't ask here!" and provides a list of sites where one can get answers to physics questions. I don't know if this is common practice for physics articles. But I wonder if it's a good idea. Questions from readers can help indicate what should be better explained in the article. For example, if someone asks, "So what is a black hole made out of, exactly?" that indicates the subject is not adequately addressed in the article. It's often difficult for editors to put themselves in the position of someone who knows nothing about the subject matter and imagine what that person might not understand. I remember on Talk:Baseball, a reader asked something along the lines of how many points you get for reaching each base. That indicated the article did not properly explain the basic concept of how runs are scored. -- Mwalcoff (talk) 03:08, 17 July 2009 (UTC)

From what I can recall, the template was added because the talk page was inundated with questions from people who hadn't thoroughly read the article and hadn't read the talk page (the same questions would come up over and over). While I agree in principle that questions could point to flaws in the article, in practice, for this article, I think the template is justified. The vast majority of the questions that showed up at Talk:Black hole should have been at Wikipedia:Reference desk/Science instead. --Christopher Thomas (talk) 05:42, 17 July 2009 (UTC)

On the positive side, most of the links related to the template look like really good ones. One could probably do well, asking a physics question at any one of those links, except for the first one - they are no longer taking any questions. However, browsing through the questions and responses listed at the first site may be of help. In any case, I think the editors at that article have provided some really good resources. IMHO. Ti-30X (talk) 00:01, 18 July 2009 (UTC)

The Wiki History of the Universe in 200 Words or Less

Here is something that is based on Eric Schulma's The History of the Universe in 200 Words or Less. The Wiki history has all the words linked to a Wiki physics, astrophysics, or other article, relevant to the link. It is interesting, and I think humorous, because it is a very witty piece written by Eric Schulman. Here is the link to the Wiki History of the Universe.... Ti-30X (talk) 03:15, 18 July 2009 (UTC)

Introduction to quantum mechanics

There is a discussion at Talk:Introduction to quantum mechanics (mainly between two editors) on how a good introductory article to quantum mechanics should look like. Now we have two competing versions, Introduction to quantum mechanics and Basic concepts of quantum mechanics. I am not too keen on studying the long-drawn-out discussion, but in particular, I am not a physicist, so I cannot really judge any inaccuracies. Is there someone to take pity on the two articles? :-) I guess there is a lot of good content in both, but the two should be well dissociated (Is that correct English?) or merged. -- Momotaro (talk) 13:46, 19 June 2009 (UTC)

Momotaro, I just noticed your question. Yes, that is very correct English. Ti-30X (talk) 20:15, 29 June 2009 (UTC)

Thanks. :-) -- Momotaro (talk) 08:44, 3 July 2009 (UTC)

A bit late, but I agree with you - I've put a merger proposal on the page, will try to follow it up. Any helpful thoughts from WP Physics folks would be appreciated! Djr32 (talk) 19:48, 20 July 2009 (UTC)

Changes to popular pages lists

There are a few important changes to the popular pages system. A quick summary:

• The "importance" ranking (for projects that use it) will be included in the lists along with assessment.
• The default list size has been lowered to 500 entries (from 1000)
• I've set up a project on the Toolserver for the popular pages - tools:~alexz/pop/.
  • This includes a page to view the results for projects, including the in-progress results from the current month. Currently this can only show the results from a single project in one month. Features to see multiple projects or multiple months may be added later.
  • This includes a new interface for making requests to add a new project to the list.
  • There is also a form to request a change to the configuration for a project. Currently the configurable options are the size of the on-wiki list and the project subpage used for the list.
• The on-wiki list should be generated and posted in a more timely and consistent manner than before.
• The data is now retained indefinitely.
• The script used to generate the pages has changed. The output should be the same. Please report any apparent inconsistencies (see below).
• Bugs and feature requests should be reported using the Toolserver's bug tracker for "alexz's tools" - [1]

-- Mr.Z-man 00:28, 12 July 2009 (UTC)

Thanks, that will be very usefull!Headbomb {^ταλκ_{κοντριβς} – WP Physics} 17:13, 20 July 2009 (UTC)

Should Variational principle#Variational principle in quantum mechanics be merged into Variational method (quantum mechanics)?

(See Talk:Variational principle. --A. di M. – 2009 Great Wikipedia Dramaout 12:11, 18 July 2009 (UTC))

Standard Model

I downloaded a new image of the Standard Model from Fermilab a little while ago. It has the Higgs Boson. In case you are interested here is the link at Wikimedia Commons: Fermilab Standard Model. It also over at the Standard Model (physics) category for images. Ti-30X (talk) 02:42, 9 July 2009 (UTC)

Interesting. I'm not entirely sure it's appropriate for Wikipedia however, as it might leave impressions that the Higgs someone the origins of all other particles.Headbomb {^ταλκ_{κοντριβς} – WP Physics} 03:53, 9 July 2009 (UTC)

Yeah, you would not want someone to jump to the conclusion that the Higgs boson is the God particle. :) JRSpriggs (talk) 06:04, 9 July 2009 (UTC)

LOL! of course I was thinking of the hypothesized particle, the Higgs boson along with the Higgs Field. Personally, I am hopeful the Large Hadron Collider can give us evidence of the HIggs boson. Of course I suppose it could go either way. But, I thought that I read somewhere that CERN began to discover evidence that tentatively suggeste the exsitence of the Higgs before it had to shut down. Maybe that source was unreliable. Ti-30X (talk) 01:27, 10 July 2009 (UTC)

If I remember correctly, they'd made statements to the effect that they'd found 2-sigma evidence for it (evidence that has about a 5% chance of having occurred by chance). Normally, proof of a particle's existence requires 6-sigma evidence (extremely unlikely to be chance). It's been a while, so I might be misremembering the confidence values they claimed, but long story short, they were getting tantalizing hints, and wanted to keep looking with their existing accelerator rather than be shut down for several years for the upgrade and maybe have someone else scoop them on the result. As far as I know, we're still looking for it. --Christopher Thomas (talk) 04:16, 10 July 2009 (UTC)

You need to be careful with confident levels in HEP. They usually refer to the confidence in a single channel. That means that 5% of the channels you are observing will show 2 sigma signals even if what you are getting is pure noise. Hence finding a 2sigma signal doesn't really mean that much in HEP. (TimothyRias (talk) 10:31, 10 July 2009 (UTC))

At least one experiment at LEP saw a tantalizing hint near the end of its run, while at least one other did not. What was seen wasn't anything conclusive at all -- essentially a "bump" that could either be the beginnings of a signal or just a random fluctuation -- but the committee in charge of LEP was convinced to extend the run (and delay the beginning of the conversion to the LHC) for at least a month. The "bump" didn't get more convincing during that extension, so LEP was shut down for good. If I recall correctly, in later, more complete analyses, the bump pretty much disappeared, suggesting it was in fact just a random fluctuation. But it's been a while since I heard this (from this four-year old talk, "The Higgs Saga at LEP" by Pippa Wells of CERN), so I may be misremembering some details. -David Schaich ^Talk/_Cont 23:15, 21 July 2009 (UTC)

Fine image, but we should all agree that it's promotional literature (at least in part). The particle physics community (Fermilab in particular) has a vested interest in people thinking the Higgs is incredibly important. --Steve (talk) 07:01, 11 July 2009 (UTC)

Help with an anonymous IP

I could use a bit of help responding to talk page posts by 76.126.215.43 (talk · contribs · WHOIS). They _sound_ reasonably well-educated, based on their posts at Talk:Magnetic monopole (among other things), but 1) they've mostly made hostile critiques of articles, rather than proposing helpful corrections, and 2) for the two talk threads I responded to (at Talk:Antimatter and Talk:Electroweak interaction), they seemed to be missing a couple of rather basic concepts.

Long story short, I'd appreciate it if someone with more expertise than I have could respond to Talk:Magnetic_monopole#Is_this_just_a_silly_topic.3F, Talk:Gravitational_interaction_of_antimatter#Are_Physicists_retarded.3F, and Talk:Bell's_theorem#Cute_theorem_but_trivially_refutable.3B_why_so_much_space.3F. There's also some borderline-trolling at Talk:Earth's atmosphere diff, though I'll assume good faith, as they seem to have adopted a somewhat less-hostile tone as time has gone on. --Christopher Thomas (talk) 22:51, 19 July 2009 (UTC)

I replied to all three, for what it's worth. -- BenRG (talk) 21:21, 20 July 2009 (UTC)

Thanks. --Christopher Thomas (talk) 23:13, 20 July 2009 (UTC)

Christopher, I'll be coming over to see if I can lend a hand. Ti-30X (talk) 11:33, 21 July 2009 (UTC)

Black hole information paradox

An anonymous IP has recently added Main approaches to the solution of the paradox to the article Black hole information paradox.

Looks very OR-ish to me, but maybe not such a bad idea in principle. Would anyone care to take a look? Jheald (talk) 08:49, 22 July 2009 (UTC)

Although unsourced it seems fairly accurate. (Some of the advantages and disadvantages mentioned are not the first thing I would mention about each option, but that is mostly a matter of taste.) It pretty much covers the options I know of, and I think it should be possible to source most of the claims being made. Many of what is said belongs to the general lore of the field, which may make sourcing the some of the statements somewhat hard if we cannot find a good recent review of the subject. (this is the typo of knowledge that is transmitted through workshops and conferences not through papers.) There definitely is no OR going on.

Ofcourse, the section could use some work. Each of the approaches should probably be worked out as a three paragraph subsection: 1)explaining the approach, 2)the advantages 3)the disadvantages. (TimothyRias (talk) 10:18, 22 July 2009 (UTC))

Stuff that is missing in a lot of physics articles

As I've been reading a lot of the articles about physics, I have noticed that a lot of basic information is missing, or is hard to find without reading through the entire article. For example, in articles about physical quantities, I think some of the most important things are that it should be easy to find: 1. which sign (letter) is usually used for that physical quantity, 2. the unit of that physical quantity, 3. how to calculate its value as a function of other physical quantities (if possible) and 4. as many ways as possible that the physical quantity is commonly used in. Often when you open an article about a physical quantity, you are only looking to find one of the two or three first of these things. However, it is not always that easy to find, if even present in the article. Often it is hidden somewhere in the text.

What really should be done is that, for example, in every article about a physical quantity, it should be made sure that at least the first three of these things are easy to find.

To help making this a reality, we should make more use of physics infoboxes. There is already a proposed infobox for units, which is great; it should be approved and then it should be made sure it comes to use. We also need an infobox for physical quantities, similar to that one.

What can be done about this? What is done about this today? Is this anything WikiProject Physics deals with or can deal with? If not, is there any other Wikipedia project which has this aim today? Otherwise one should be started. A lot of physics articles need this type of maintenance. But it is worth it, I promise.

--Kri (talk) 12:35, 24 July 2009 (UTC)

My experience is that most articles on units and quantities have not been worked on much and could use a lot of work. Having some good standardized infoboxes for these articles may provide some backbone for these articles. I'll try to whip up a {{Infobox Unit}} later today following that 3 year old proposal.

Moreover, many of these article tend to fall in between projects. WikiProject Meaurement may also be a good place to bring this up. (TimothyRias (talk) 13:03, 24 July 2009 (UTC))

Coulomb
Unit system	SI derived unit
Unit of	Electric charge
Symbol	C
Named after	Charles-Augustin de Coulomb
Conversions
1 C in ...	... is equal to ...
SI base units	1 A s
CGS units	2997924580 statC
Natural units	6.242×1018 e

OK, how about something like this? Most of the parameters are optional so the last few items do not need to be included in tautological cases like this one. Any suggestions for other items? (TimothyRias (talk) 13:46, 24 July 2009 (UTC))

Definitely a good start. I was thinking it might also be useful to add the Geometric Unit System , Am I right? Harharvoxels (talk) 02:12, 1 September 2009 (UTC)

How many electrons are in -1 Coulomb? JRSpriggs (talk) 16:39, 24 July 2009 (UTC)

The charge on an electron is considered to be the elementary charge (ie none smaller can be detected - despite quarks having 1/3 or 2/3 of that charge). This elementary charge e is ~ 1.602 x 10^-19 C. Protons have a charge of the same magnitude. Abtract (talk) 21:08, 24 July 2009 (UTC)

That seems really good! We could use a similar one for physical quantities (which we can put in the electric charge article!), I shall make a proposal for one later. What we really need is an organized attempt to improve every article in this way – just put in one of those infoboxes in every article which needs one. Later on when we see that it works some other criterias for maintaining good physics articles can be added as well. Probably a new wikiproject would be the best for this reason, anyone who knows how to start one? --Kri (talk) 21:24, 24 July 2009 (UTC)

Electric charge
Common symbols	Q
SI unit	Coulomb
Derivations from other quantities	Q = I · t

Ok, I have now created an Infobox Physical quantity, it is a little bit small compared to that one for units, but what more is needed? Anything more you can come to think of? Couldn't come up with anything more. It has now been proposed on the proposal page.

By the way, now when the infobox templates are finished, do they even need approval, isn't it just to use them? --Kri (talk) 00:27, 25 July 2009 (UTC)

You're in the clear. Nothing special needed to use them. Also the relevant project would probably be WP:MEASURE.Headbomb {^ταλκ_{κοντριβς} – WP Physics} 00:38, 25 July 2009 (UTC)

I guess the issue raised by JRSpriggs is that there may be other common nonstandard units in which a unit may be commonly expressed. That is a good point. I could simply add an "other units" parameter. A more sophisticated approach would be to add "otherunit=" and "inotherunit=" parameters allowing custom defined units. How many of these should I add? 2 or 3 probably would suffice, and with them in place more can easily be added as needed without breaking the template for article already using it.

I could also replace all the inXXXunits options with pairs "unit1=" and "inunit1=", what would be preferable? (TimothyRias (talk) 15:14, 25 July 2009 (UTC))

So -1 C = 6.242×10¹⁸ electrons. Which fact should be included in the table. JRSpriggs (talk) 15:28, 25 July 2009 (UTC)

I have used the last option to make the template more flexible. See template documentation for details. (TimothyRias (talk) 08:25, 27 July 2009 (UTC))

Well, now we have created two infobox templates, that is great. Currently no articles are using them, so, what is needed to get these templates to use? Is it possible to start a new project, or a subproject, which aims to make every physics article have certain information easily accessible, and which puts some requirements on every article (depending on what type of physics article it is)? How should we make these templates come to use? I shall start myself (so long) to implement these wherever I feel they are needed. --Kri (talk) 20:33, 25 July 2009 (UTC)

By the way, do you think some of the names of the arguments should be changed? For example, "derivations" in the Infobox Physical quantity, I don't know if that is the best name for that variable. Probably the names should be changed as fast as possible if they need to be changed. Anyway, I'm starting to use the templates, we will just have to find all implementations later and change in them at the time. --Kri (talk) 20:44, 25 July 2009 (UTC)

I don't know why you are talking about creating a project or subproject just to add a few infoboxes to a few pages. That would be very unusual, a waste of resources, and unlikely to succeed. The way to do it is to do it. (I am not going to do it, though, as I am busy with other things.) Hans Adler 20:59, 25 July 2009 (UTC)

Here is what you need to do:

1. Extract list of physical quantities and units from List of physical quantities see also the category:physical quantities
2. Copy these into 2 lists on your user page (one for quantities; the other for units)
3. Post the link here and invite others to go through list scratching off <s></s> ones they have done
4. Optional: get Wikipedia:AutoWikiBrowser if you can to help speed the process up
5. Check the results and make changes. there is a template:done template

TStein (talk) 17:57, 27 July 2009 (UTC)

We also have to be careful with incompatible units, e.g. the CGS unit of charge is not dimensionally compatible with the SI unit of charge. The conversion factor in the table is thus not useful (because CGS doesn't mean that we can only use centimeters, grams and seconds). It is better to say that q_{si}/sqrt(4 pi epsilon_0) -----> q_{cgs}. Count Iblis (talk) 19:08, 27 July 2009 (UTC)

I agree with Count Iblis...for example, the template above ("Coulomb") should say "2997924580 statC × sqrt(4pi epsilon_0)".

Also, maybe conversions should be in the table? Or a separate/add-on template? For example, the left column could say conversions and the right column could say

1 atm = 101325 Pa

1 bar = 100000 Pa

1 torr = 133.322 Pa

1 psi = 6.894×10³ Pa

Obviously for pressure, there's too many units to list every pair...But even just conversions into SI would be nice. But come to think of it, maybe every pair could be included by using show/hide boxes or something along those lines. (i.e., you select "Pa" to see all units expressed in Pa like above, or instead you select "atm" to see all units expressed in atm, and so on.) That would be really nice if it could be done in an elegant and unobtrusive way...wiki-syntax challenge anyone? :-) --Steve (talk) 00:48, 28 July 2009 (UTC)

You don't have to include every pair. On the Pascal page it is not relevant how to express an atm in a psi, just how to express Pa in atm and psi etc. (TimothyRias (talk) 08:04, 28 July 2009 (UTC))

Personally, I think having conversions and/or expressing the unit in other system is too complicated. I would prefer to have just the units with a link to the relevant article. For example:

Name: Pascal

Abreviation: Pa

Unit of: Pressure

Named after: Blaise Pascal

Type: SI derived unit

1 Pa = 1 N/m²

Common units of pressure:

pascal, Torr, psi, atmosphere, bar

Description: A small unit of pressure. Atmospheric pressure is around 100,000 Pa

I added the description category here as well just to see how it would work and as an idea to allow both for simplicity and for flexibility. TStein (talk) 18:33, 28 July 2009 (UTC)

A lot of your proposals seem nice! I am on a vacation right now. Maybe I will create a page on my user listing articles that still need infoboxes when I get back from the vacation, if not anybody else has done it before. There are some things that may be good to discuss, for example, are the infoboxes finished enough for starting to put them in a lot of articles, or do we have to change something in them before? In that case I guess it is just to start using them. --Kri (talk) 20:21, 29 July 2009 (UTC)

Hello, I'm back from the vacation now. The reason I wanted to start a project (because it really is a big project) was that I wanted something to happen, quickly. So that something big could be organized that would improve all physics articles that needed to be improved. If you look at which pages that link to the physical quantity infobox, and pager that link to the unit infobox, you see that it is not especially many (basically just the pages I have put them on). And I am not going to do it myself, because it is a lot of articles, a lot of articles that would benefit from this service. So, what I wanted was basically help putting up something that could do a lot of work (i.e. putting these templates in all the proper articles, and maybe other stuff like administration too); maybe if I'm lucky the measurement project can take care of it. What needed to be done was to standardize these articles, and create certain minimum demands for them. That would really improve them a lot.

However, my interest has cooled down. This project is yours now; if some other people feel like taking over, that would be great. Or maybe it should be left like this, I mean, it hasn't happened especially much. What I asked for before has not been returned. I asked for a project, but apparently it wasn't worth spending that much attention on it. We at least have two working (I guess) infobox templates now, and hopefully they could also start to be used eventually if people think they will do any good. --Kri (talk) 10:16, 10 August 2009 (UTC)

Oh, and if anybody wants me something, he can contact me on my talk page. I'm removing this page from my watch list now. --Kri (talk) 10:20, 10 August 2009 (UTC)

Sorry, didn't mean to sound ungrateful, what I meant was just that I had a little bit to high expectations on this. Maybe I was a little bit to unpatient. And then I became disappointed when I realized it wasn't going to work. But what do I know, Rome wasn't built in one day. :) Should we try, just as a test, and see how many articles use the templates in one month from today? Currently, 6 articles are using the physical quantity infobox (Electric charge, Force, Shear stress, Shear modulus, Shear strain and Viscosity), and 3 pages are using the unit infobox (Kilogram, Coulomb and Pascal (unit)). Today it is the 12:th of August, so, let's check again the 12:th of September. --Kri (talk) 12:06, 12 August 2009 (UTC)

Hm, today happens to be the 12:th of September. Apparently no more article has implemented the physical quantity infobox. --Kri (talk) 11:13, 12 September 2009 (UTC)

(undo indent) Someone with AWB privileges can probably do this really quickly. Once we get a template settled. TStein (talk) 17:46, 12 August 2009 (UTC)