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High energy physics

I am very uncomfortable with High energy physics being just a redirect to the particle physics page. I feel HEP deserves an article by itself, being one of the largest sub-fields of physics. However, I'm having trouble finding good, comprehensive reviews/sources to start the article off with. I have started a "proto-article" in my userspace and I'd really appreciate if anyone could help with expansion (I'll take it "live" as soon as it looks viable). Any new ideas are welcome.

Thanks, SPat ^talk 20:15, 26 May 2012 (UTC)

I could provide sources but they would just refer to particle physics... No expert yet, so I can't see any further than HEP as experimental particle physics... F = q(E+v×B) ⇄ ∑_ic_i 22:35, 26 May 2012 (UTC)

I'm not sure about this. To physicists "High Energy Physics" is virtually a synonym of "Particle Physics", even though they have very slightly different meanings. Also "Nuclear Physics" tends to be regarded as a separate subject now, rather than being part of HEP. CodeTheorist (talk) 22:27, 12 June 2012 (UTC)

They are not generally synonym. For example, String theory and quantum gravity are high energy physics subjects, which are not really particle physics. TR 22:33, 12 June 2012 (UTC)

You are quite correct, but string theory and QG tend to get lumped in with "Particle Theory". From the Particle Physics page: "A third major effort in theoretical particle physics is string theory". CodeTheorist (talk) 22:43, 12 June 2012 (UTC)

At the very least, one of those two articles should mention this (the fact that the terms are sometimes used synonymously). IMO the fact that at least some sources distinguish is reason enough for a separate article. SPat ^talk 23:06, 12 June 2012 (UTC)

Two-body Dirac equations

This is a new article first requested for creation by a new editor Hcrater, then declined, then Hcrater wrote it anyway, citing to his own sources i.e. WP:OR. It was painfully vague and genuinely nonsense - I tried to clear it up, remove the OR refs and tagged it as OR. A link on Dirac equation was added to link there - evidently promotion of work. If anyone can find references, please add them, and continue to clarify the article. There is one that does not seem to be OR. I have also warned the user of this on his talk page. Thanks. F = q(E+v×B) ⇄ ∑_ic_i 14:08, 11 June 2012 (UTC)

Note, that in principle it is not forbidden to add references to one's own work. This is especially true if your papers belong to to most highly cited works on the subject in the literature, as is the case with the work of Crater here. The more relevant question is whether the topic is relevant enough (which it appears it may be). May I ask, that you be careful in not antagonizing potential expert contributors to the project.TR 15:30, 11 June 2012 (UTC)

I'm sorry, and will apologize to him and restore the references. Just being "too careful". F = q(E+v×B) ⇄ ∑_ic_i 16:29, 11 June 2012 (UTC)

Done. F = q(E+v×B) ⇄ ∑_ic_i 16:34, 11 June 2012 (UTC)

My impression is that the subject is notable but the article is seriously unbalanced, with far too many citations of the same author. Also, the Breit equation is another approach to the same problem and has priority by several decades. RockMagnetist (talk) 17:28, 11 June 2012 (UTC)

RockMagnetist - thank you for adding the sources and cleaning up the refs/external links. Unbalanced (and inaccurate by dates of publication, 1920s/1980s) is indeed the problem. F = q(E+v×B) ⇄ ∑_ic_i 23:10, 11 June 2012 (UTC)

I thought that multiple particles were supposed to be handled by quantum field theory where the wave function of the one-particle case is replaced by the annihilation operator. JRSpriggs (talk) 06:43, 12 June 2012 (UTC)

Yes, the standard textbooks will say that relativistic bound state problems cannot be treated via Schrödinger type equations and a full field theoretic approach is needed (see e.g. Chapter 10 of Itzyckson & Zuber, to lowest order you can use the Dirac equation but to obtain radiative corrections you need to tackle the full field theoretic problem). Now, from the article, it seems that there are new results allowing one to greatly simplify such calculations to some approximation by using wave-equations in some way. But the article does not go into details. Count Iblis (talk) 19:50, 12 June 2012 (UTC)

It seems to me that you would need to make the wave function depend on at least seven continuous independent variables: x₁, y₁, z₁, x₂, y₂, z₂, t. But the article says nothing about what independent variables are used. JRSpriggs (talk) 05:06, 13 June 2012 (UTC)

Modified langle and rangle templates for inline angular brackets

These templates are currently in the database as unused: for ⟨ see p.6 no 5579 and for ⟩ see p.9 no 8935. Recently after reworking them (and wasting a silly amount of time messing around with aligning things, which shouldn't have happened), I added them to ⟨|⟩.

Aesthetically they look ok (sort of), but the concern is they may cause spacing irritations, due to the glyphs in the template (but these are the closest ones matching angular brackets).

What do others think? Any objections to usage? If not I plan to implement them mainly in QM articles. WikiProject Mathematics has been notified. F = q(E+v×B) ⇄ ∑_ic_i 12:27, 13 June 2012 (UTC)

The glyphs have been updated to the correct angle brackets. F = q(E+v×B) ⇄ ∑_ic_i 15:23, 13 June 2012 (UTC)

Both the in and out parameter descriptions say "(i.e. behind the vertex of the bracket)" on both templates. Once that's fixed, I don't particularly have any objections. 786b6364 (talk) 16:23, 13 June 2012 (UTC)

Fixed. F = q(E+v×B) ⇄ ∑_ic_i 21:55, 13 June 2012 (UTC)

Sorry, one more thing. I'm not sure what your point is in the tables section of the docs. Is there any difference between, for instance, ψ{{rangle}} and {{rangle|in=ψ}}? Are you saying that it only matters if you're using vertical bars in tables? Does using or not using the html entity make any difference? 786b6364 (talk) 22:37, 13 June 2012 (UTC)

The point is to show that the vertical bar can interfere with the table coding, because | and not | is used in the tables. Notice how some bits don't show up where they should? F = q(E+v×B) ⇄ ∑_ic_i 23:17, 13 June 2012 (UTC)

The reason for the in/out parameters was to position the contents in/out the brackets as accurately as possible, because of the bad spacing problems with the original glyphs 〈 and 〉 (which are actually Chinese punctuation symbols). They are now redundant so no there is no difference between ψ{{rangle}} and {{rangle|in=ψ}}. The parameters will be removed. F = q(E+v×B) ⇄ ∑_ic_i 23:22, 13 June 2012 (UTC)

Done, also the bra-ket article has been reverted for now. F = q(E+v×B) ⇄ ∑_ic_i 23:50, 13 June 2012 (UTC)

Alright, the docs look much clearer now. Thanks! 786b6364 (talk) 00:03, 14 June 2012 (UTC)

No worries, thanks for pointing these out, and for any edits you make that fix my typos (probably millions). =) F = q(E+v×B) ⇄ ∑_ic_i 00:28, 14 June 2012 (UTC)

Just as a note that the size of the brackets should be specified in ems rather than px. I'm not sure what the exact desired size is for them or the conversion in this case to px, so I held off on editing the templates myself. --Izno (talk) 00:59, 14 June 2012 (UTC)

Luminiferious aether

Some comments at

• Talk:Luminiferous aether#Einstein's views
• Talk:Einstein's views on the aether

are appreciated. Thanks. --D.H (talk) 14:56, 17 June 2012 (UTC)

Merge comment requested - Superhydrophobe

Are Lotus effect and Superhydrophobe talking about the same thing? Should they be merged? Please comment at Talk:Superhydrophobe. D O N D E groovily Talk to me 02:54, 18 June 2012 (UTC)

A recent edit

I am wondering if this recent edit by an anonymous IP at Finite-difference time-domain is appropriate. ---- Steve Quinn (talk) 01:42, 20 June 2012 (UTC)

I don't see what the problem is. Xxanthippe (talk) 02:30, 20 June 2012 (UTC).

As-written that addition seems overly-broad and makes connections that may or may not actually reflect historical development. I'll attempt to rewrite it. Anyone intimately familiar with the field is free to revise it, of course, but detailed discussion of the history of and relations between such techniques should probably be left to the Numerical analysis article. --Christopher Thomas (talk) 02:39, 20 June 2012 (UTC)

Fluid structure interaction

Article Fluid-structure interaction states that "reed makes sound because the equations governing it have oscillatory solutions". I beg to differ. The reed knows nothing about equations which are just something humans use to understand nature. Instead the reed could just be presented as an example of fluid structure interaction without further ado about why it happens to make sound. Also statements like "equations that govern nature" in other articles should be rephrased so that they don't imply that humans decide how things work.

BR, Anonymous — Preceding unsigned comment added by 130.188.8.27 (talk) 13:46, 26 June 2012 (UTC)

Thermonuclear weapon

Hello,

I started a requested move of Teller–Ulam design to Thermonuclear weapon. Feedbacks are very welcome. -- Taku (talk) 23:57, 30 June 2012 (UTC)

These are not exactly the same topic because there are other possible designs for fusion weapons. For example, the fission trigger could be built in a sphere around the fusion core. Or Lithium deuteride could be replaced by other substances capable of fusion.

So I would suggest a more general article on thermonuclear weapons with a link to this particular design (which is the most commonly used). JRSpriggs (talk) 19:11, 1 July 2012 (UTC)

Don't we already have a general article at nuclear weapon design? That article already mentions fusion-boosted fission weapons (the spherical type), and links to Teller-Ulam design (from its "two-stage thermonuclear weapons" paragraph). In fact, the article looks well-written enough to be worth trying to polish to featured status IMO.

Regarding fuels other than lithium deuteride, that was only tried once to my knowledge (the Ivy Mike test). LiD turns out to be by far the most practical fuel for weapons. --Christopher Thomas (talk) 19:35, 1 July 2012 (UTC)

Escape velocity - scalar or vector ?

As part of a rewrite of sections of the escape velocity article, Zedshort (talk · contribs) wrote

"Escape velocity is a velocity in that it is the radial speed an object must have as it is directed radially away if it is to escape another mass's) gravitational pull. The escaping object may have an additional component of velocity normal to its radial velocity but in order to escape the planet's gravitational pull, it must have a speed in the radial direction at least as great in magnitude as the mass's "escape velocity"".

This idea that escape velocity depends on direction seemed to me such a fundamental error that I reverted their rewrite, explaining why on the talk page. In response, Zedshort says

"You are incorrect. Escape velocity is not just a speed but has a direction making it a vector quantity. The component of the speed in the radial direction must be equal to the escape velocity in magnitude."

To avoid a pointless back-and-forth argument, I would welcome other editors' input at Talk:Escape velocity#Reversion of rewrite. Gandalf61 (talk) 14:59, 2 July 2012 (UTC)

Proton spin crisis

This aritcle, Proton spin crisis, looks good to me but it is outside my scope of knowledge. I am hoping that someone who is well versed in this subject could have a look. I am seeing more self published articles on google scholar than anything else so I really don't know how mainstream this topic is. Thanks ---- Steve Quinn (talk) 19:18, 3 July 2012 (UTC)

The article seems plausible, and the editor that created it seems to be acting in good faith, but it might be a good idea to have someone very politely explain WP:COI to this person. They've spent quite a lot of time creating and revising Eliyahu Comay (edit | talk | history | protect | delete | links | watch | logs | views), and a paper from that person is cited as one of the references in the "latest findings about the spin crisis" subsection. Given that their username is Ofercomay (talk · contribs), it's raising flags for me.

That said, the user appears to know their field and be making what seem to be good contributions, so please do try to work constructively with them. WP:COI doesn't forbid writing about your own work (if that's what's happening here), it just says to be careful when doing it.

More thorough vetting would involve a particle physics type doing a literature search, to make sure that the references cited reflect the more prominent references in literature. I'm not in a position to do that. --Christopher Thomas (talk) 20:42, 3 July 2012 (UTC)

I am rather worried about the fact that the cited Comay paper is published in Progress in Physics. This tends to be a red flag for its contents not being widely endorsed.TR 21:41, 3 July 2012 (UTC)

As that and an arxiv preprint are the only references for the "latest findings" section, it's probably worth sticking a "needs improvement" template on that section and starting a talk page thread about it. A literature review would still be handy. --Christopher Thomas (talk) 22:27, 3 July 2012 (UTC)

Actually the other reference in that section is a PRL with over 50 citations. It is just the last bit that seems dubious.TR 06:36, 4 July 2012 (UTC)

Agreed. Xxanthippe (talk) 06:47, 4 July 2012 (UTC).

Would you mind updating the reference, then? The present citation gives no indication that the paper was actually published. --Christopher Thomas (talk) 06:52, 4 July 2012 (UTC)

huh? It says right there: " Interplay of Spin and Orbital Angular Momentum in the Proton. Physical Review Letters, 101, 102003 (2008)".TR 07:34, 4 July 2012 (UTC)

Apparently I'm more tired than I thought. I withdraw my comment. --Christopher Thomas (talk) 11:12, 4 July 2012 (UTC)

The Proton spin crisis is an important topic in physics with a substantial literature and deserves an article. The Comay paper does does not have enough cites in Google scholar to be considered a significant contribution to the subject (incidentally, it should be orbital, not spatial). Xxanthippe (talk) 23:02, 3 July 2012 (UTC).

Can we get some help at Time?

I have recently come upon the article Time and found that the lede definition (the very first sentence) was written strictly from the POV of experimental physicists, essentially saying that time is a measurement. The lede said nothing about how time is normally experienced by humans (and other beings) as, for lack of better words, our sequential progress in our existence. This is what is in the primary definitions of all three major English dictionaries. It's highly POV to require the lede definition of time to be defined only in terms of measurement. As if time has no meaning outside of measurement. Especially when it ignores the dictionary definition and especially when there exists a Time in physics article.

Primary definitions from 3 English language dictionaries:

thefreedictionary.com (obviously drawn from AH)

a. A nonspatial continuum in which events occur in apparently irreversible succession from the past through the present to the future.

b. An interval separating two points on this continuum; a duration: a long time since the last war; passed the time reading.

c. A number, as of years, days, or minutes, representing such an interval: ran the course in a time just under four minutes.

d. A similar number representing a specific point on this continuum, reckoned in hours and minutes: checked her watch and recorded the time, 6:17 a.m.

e. A system by which such intervals are measured or such numbers are reckoned: solar time.

Merriam-Webster Dictionary

a : the measured or measurable period during which an action, process, or condition exists or continues : duration

b : a nonspatial continuum that is measured in terms of events which succeed one another from past through present to future

American Heritage Dictionary

a. A nonspatial continuum in which events occur in apparently irreversible succession from the past through the present to the future.

b. An interval separating two points on this continuum; a duration:a long time since the last war; passed the time reading.

c. A number, as of years, days, or minutes, representing such an interval:ran the course in a time just under four minutes.

d. A similar number representing a specific point on this continuum, reckoned in hours and minutes:checked her watch and recorded the time, 6:17 AM.

e. A system by which such intervals are measured or such numbers are reckoned:solar time.

Oxford English Dictionary (1971 Compact Edition)

1. A limited stretch or space of continued existence, as the interval between two successive events or acts, or the period through which an action, condition, or state continues.

Can we get some help there at Time? 71.169.176.253 (talk) 14:45, 4 July 2012 (UTC)

Before anyone makes any drastic changes, I suggest digging through the archives at Talk:Time, as I remember a long-running debate about the topic from a few years back. If memory serves, most of the article was written from a philosophical rather than measurement perspective back then, though it's possible that I'm misremembering. Either way, most of the discussion should be happening on that page (and if possible contain a summary of the old threads about the debate for context). --Christopher Thomas (talk) 22:03, 4 July 2012 (UTC)

Davisson-Germer experiment

Can somebody check if the image at Davisson-Germer experiment is ok?? I believe I have addressed the main points(see talk page for details). Please check if there is any correction/addition that needs to be done. Thanks. Roshan220195 (talk) 17:12, 4 July 2012 (UTC)

One more thing, "I would like to comment that the essential conclusion of this article is actually wrong according to Davissons and Germers original articles. Since Davisson and Germer worked with low energy elektron diffraction, LEED, it is not possible to use the Bragg equation in the way given in the article. This is due to the wavelength dependent refraction index of the nickel crystal." was a comment added in the talk page. Is this right?? — Preceding unsigned comment added by Roshan220195 (talk • contribs) 19:45, 4 July 2012 (UTC)

I don't have the expertise to tell, but it sounds like it could be a legitimate concern. If someone with a library near them digs up the original article about it, that should provide an easy way to check the wiki article's formulae. --Christopher Thomas (talk) 05:25, 5 July 2012 (UTC)

Does a theory "give" mass to anything?

I've read a few articles on this here site relating to the newly announced --- possibly discovered --- Higgs particle. One thing that strikes me is the way the mechanism or theory is described as "giving" mass to particles. I'm not sure if my objection is technical, scientific, or down right linguistic, but can a theory really give away physical properties? I would have said, for example, this or that theory tries to explain how this or that thing has a mass. Could it be recommended that articles within this project don't endow too many human faculties on a piece of paper? Verbs are simple but all so complicated... Eddi (Talk) 23:23, 5 July 2012 (UTC)