Wikipedia talk:WikiProject Physics/Archive July 2013

Flame rectification

I'd greatly appreciate it if we could have some expert eyes on the flame rectification article. I've put in the explanations given by references from the gas heating industry, per WP:RS, but I don't think these tell the full story about what's going on in this phenomenon.

As far as I can see, there has to be some other sort of asymmetry in the system apart from the charge carrier asymmetry to make this work, as otherwise, by the principle of symmetry, you might expect current flow to be the same in both directions between an identical pair of symmetrically placed electrodes. Clearly there is, since millions of the flame sensors are in use around the world, but what is the important factor here that makes this work, and what in detail is physically going on in the system to make this happen?

Most non-RS web discussions about this suggest that the key thing here is having electrodes of radically different sizes, but even they fail to give a truly convincing explanation of how it works. Some, instead, seem to suggest that some kind of coating is needed on one electrode eg. [1]. (I can also speculate that the placement of the electrodes upstream/downstream in the flame might be another asymmetry that might make a difference, but no-one else seems to have had this idea.) I'm surprised by the apparent absence of any mention of this plasma physics phenomenon in the academic literature: perhaps I've been searching for the wrong keywords? Any help you can give would be much appreciated. -- The Anome (talk) 09:51, 29 June 2013 (UTC)

Didn't Faraday first notice this? Andy Dingley (talk) 11:01, 29 June 2013 (UTC)

Quite possibly, but what I'm amazed by is that there doesn't seem to be any scientific literature on this phenomenon. I can think of several reasonably physically plausible explanations for why in might happen, but that's just idle speculation, not actual scientific knowledge. I find it hard to believe that some plasma physicist, or at least someone outside of the gas-appliance design community hasn't investigated this experimentally and written it up: or is the result such a trivial consequence of basic plasma physics (which I'm reading up on now) that no-one even thinks it worth mentioning, even as a topic for an exercise? -- The Anome (talk) 17:38, 30 June 2013 (UTC)

• Got it! Actual research: http://liu.diva-portal.org/smash/record.jsf?pid=diva2:20787 , complete with full-text PDF: http://liu.diva-portal.org/smash/get/diva2:20787/FULLTEXT01.pdf

  I've now had a go at summing up the thesis' conclusions, but I'm not sure how well I've done so. Please feel free to check my working... -- The Anome (talk) 17:55, 30 June 2013 (UTC)

• Thanks for being persistent. ---- Steve Quinn (talk) 03:55, 1 July 2013 (UTC)

Dodgy articles

I'll be away for the next week or so, but can someone people have a look at these articles: Superradiant phase transition and Hopfield dielectric. This is considering that the same editor appeared to try and shoehorn similar dodgy material related to trojan wave packets into the cold fusion article, and there may be issues with regards to promotion of trojan wave packets and also fringe promotion. The editor appears to be making a lot of dodgy edits in a lot of places, IRWolfie- (talk) 00:53, 1 July 2013 (UTC)

Observable universe

See WT:AST where a request to help update the article is lodge, with a draft of the proposed changes appearing at talk:Observable universe/workpage -- 65.94.79.6 (talk) 05:51, 1 July 2013 (UTC)

Please see feedback (comments) here. Thanks. ---- Steve Quinn (talk) 19:36, 4 July 2013 (UTC)

Request from AFC

Is this guy notable? - Wikipedia talk:Articles for creation/Ali Chamseddine (2) Thanks Roger (Dodger67) (talk) 11:57, 4 July 2013 (UTC)

Transformed the redirect Irreducible representation into an article

Even just looking at the edit history, and more importantly after a discussion on my talk page, this is a desperately needed article and would help fill gaps in WP on group theory in theoretical physics and chemistry. I thought that at least something of a definition with some links and sources (to be moved inline) is far better than the annoying redirect to simple module, and decided put the draft in mainspace so others with expertise/interests in group theory can see and/or edit it. Needs a lot of work which I'll hopefully get to finish (recently busy...). M∧Ŝc²ħεИ_τlk 21:48, 7 July 2013 (UTC)

Request for move: Electronvolt

A few extra comments at Talk:Electronvolt#Requested_move_2 would be appreciated. — Quondum 10:54, 8 July 2013 (UTC)

RFC Observable universe

In an effort to get other editors involved I am placing a link to the RFC Observable universe here. Relevant diffs have been posted. Thanks. (I am also posting this over at WP:AST) ---- Steve Quinn (talk) 03:28, 9 July 2013 (UTC)

New article:Leslie Lawrence Foldy

No articles on the people who formulated the Foldy–Wouthuysen transformation in the year of 2013. Much more to follow, especially sources, although better than nothing.

For those interested, it may need confirmation of some statements, else I'll do it in time anyway. Also his real name was László Földi and while "Leslie Foldy" is an American approximation/nickname, and apparently he coined his own middle name, so we may need agreement if László Földi should be the article title (for now a redirect).

The other physicist Siegfried Adolf Wouthuysen will be created shortly hopefully. M∧Ŝc²ħεИ_τlk 17:58, 19 June 2013 (UTC)

To answer my own query, "Leslie Lawrence Foldy" is clearly easier to type and is his widespread name, so it should probably stay that way. M∧Ŝc²ħεИ_τlk 18:51, 19 June 2013 (UTC)

I agree that the article should be at his preferred name among English speakers. To confuse things, though, worldcat lists his books sometimes with L. L. Foldy and other times with L. L. Földy (but none that I can find under Földi). Laura Scudder | talk 21:01, 19 June 2013 (UTC)

Yes, the title is fine as it is. M∧Ŝc²ħεИ_τlk 12:04, 9 July 2013 (UTC)

New article:Siegfried Adolf Wouthuysen

Unfortunately, there doesn't seem to be much to say about S.A.Wouthuysen, but there are at least three links in a new article... M∧Ŝc²ħεИ_τlk 12:04, 9 July 2013 (UTC)

Gravitational potential

I do not like this bold edit in the lead. But I have not a mood to argue with IPs currently; maybe somebody else? Incnis Mrsi (talk) 07:58, 14 July 2013 (UTC)

Here is a segment of the IP's main edit:

"The gravitational potential is the gravitational potential energy of a unit mass."

... yes

"Any potential energy is by definition latent, having a zero actual value."

Isn't absolute potential energy indefinite? It can be defined zero anywhere, relative to that zero is the difference in potential energy.

"That is why the gravitational potential energy of a massive object is zero minus the potential energy that has already been actualized (i.e., converted into kinetic and thermal energies) in the process of the massive object's gravitational movement (freefall and/or contraction) to the current location."

Isn't it clearer to say the negative of the work done on the object? What does "actualized" mean?

"Therefore, the gravitational potential energy of a massive object is zero infinitely far away from any gravitational attractor (including the massive object's own centre of gravity) and negative at any finite distance."

Said above...

M∧Ŝc²ħεИ_τlk 09:11, 14 July 2013 (UTC)

I didn't realize the IPs edits were reverted... M∧Ŝc²ħεИ_τlk 09:13, 14 July 2013 (UTC)

Talk:Spacetime

I've initiated a discussion there that project members may be interested in, about a particular section of the article which I see as a tangent at best, and completely unimportant at worst. StringTheory11 (t • c) 04:37, 17 July 2013 (UTC)

WP:AN requested to topic-ban Damorbel from all articles and talk pages on thermodynamics.

Further to the previous discussion we had here in December 2012, since the exact same behaviour has kicked off yet again at Talk:Heat I have now made the formal request at WP:AN for Damorbel (talk · contribs) to be community topic banned from all articles and talk pages on thermodynamics.

The discussion can be found here. Jheald (talk) 21:49, 18 July 2013 (UTC)

Wikipedia:Articles for deletion/Hořava–Witten string theory

Wikipedia:Articles for deletion/Hořava–Witten string theory badly needs physicist input. -- 203.171.197.4 (talk) 07:29, 20 July 2013 (UTC)

We can ask our very own string theorist editor Lubos Motl for input (but then, of course, we may need to ignore anything else he has to say). Count Iblis (talk) 09:06, 20 July 2013 (UTC)

Run-by correction of “misnamed” words

When I saw [2], I pushed [rollback] because identified it as a thoughtless “correction” of the wording, that was created in several years by multiple experts, on a formal pretext of WP:EGG. But if one feels I was wrong, then make better wording, please. Of course, the post aims to alert about possible future similar “corrections” in experts-written articles. Incnis Mrsi (talk) 15:40, 24 July 2013 (UTC)
Update: While I typed this posting, the editor in question fixed a “minor editing mistake”. A volunteer to push [rollback] the second time? Incnis Mrsi (talk) 15:52, 24 July 2013 (UTC)

Condensed matter physics (again!)

I've got a lot of help for this article over here before - this time I'm thinking of pushing it towards FAC - please help with suggestions for improvement here. Thanks! SPat ^talk 05:32, 26 July 2013 (UTC)

commons:File:ProtonFiveQuarkStructure.svg

When I saw a red-faced user replacing the picture in the proton article, certainly, I first considered rollback. But it looks unusually tidy and insightful. Incnis Mrsi (talk) 10:16, 26 July 2013 (UTC)

Two considerations:

• It doesn't fit the image of other particles. Consistency would probably be preferable here.
• The subtitle of the image is wrong now, this needed to be fixed anyway.

Besides those the image is very nice, but I think this representation would need in-depth explanation (What is the red circle? what are the blue wavy lines? What is the meaning of those strange quarks? etc.) Maybe it's best to use the old image in the infobox and use the other image somewhere else in the article, were one can describe it precisely. --Patrick87 (talk) 11:07, 26 July 2013 (UTC)

I've reverted it. At best it's way too premature to include anywhere. From a quick search, the only thing I can find related to 5 quarks and protons are related to intrisic vs extrinsic properties of sea quarks doing something at high energies. Protons valence quarks are uud, which is what we show in our diagrams. Headbomb {talk / contribs / physics / books} 13:29, 26 July 2013 (UTC)

Wikipedia:Articles for deletion/Photon dynamics in the double-slit experiment

This project might be interested in Wikipedia:Articles for deletion/Photon dynamics in the double-slit experiment. -- 203.171.196.16 (talk) 01:28, 29 July 2013 (UTC)

Requesting help at AfC

Please review Wikipedia talk:Articles for creation/Dyakonov Surface Waves, particularly for Notability and Verifiability. Roger (Dodger67) (talk) 16:43, 26 July 2013 (UTC)

Somebody, anybody, please! We really need someone who understands the topic to post an opinion - on that page, not here. Roger (Dodger67) (talk) 17:16, 29 July 2013 (UTC)

Wakey wakey! Is this project dead, or just asleep? Roger (Dodger67) (talk) 09:01, 30 July 2013 (UTC)

Just because one of us knows something about physics and cares about some parts of physics does not guarantee that he will know anything about Dyakonov Surface Waves. Certainly, I have never heard of them elsewhere. So it would be inappropriate for me to review that article. As far as merely checking for the existence of the sources, you could probably do that yourself more easily than I could. JRSpriggs (talk) 10:04, 30 July 2013 (UTC)

Request for comment: Aerodynamics article organization/content

Hi all. I started a Talk section on the organization/content of the Aerodynamics article here. I'm concerned that the article currently is not very accessible/sensibly organized for a lay person (or indeed, for me either as a not-so-lay person), and it would be great to have some feedback. Corvus coronoides _talk 13:04, 29 July 2013 (UTC)

KSSOLV: The AfD needs additional input

A new article KSSOLV claiming significant applications to physics is up for deletion discussion at Wikipedia:Articles for deletion/KSSOLV. Tkuvho (talk) 12:03, 31 July 2013 (UTC)

Nomination of Dilation as field (DaF) for deletion

A discussion is taking place as to whether the article Dilation as field (DaF) is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Dilation as field (DaF) until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. See Wikipedia talk:WikiProject Physics/Archive June 2013#Dilation as field (DaF): fringe alert for a previous reference at this WikiProject. — Arthur Rubin (talk) 16:31, 15 July 2013 (UTC)