Wikipedia talk:WikiProject Physics

WikiProject Physics
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Request to merge "megasonic cleaning" into "ultrasonic cleaning"?

I recently joined Wikipedia and my first suggested edit was to Megasonic cleaning. My guess is that this article would belong better as a subsection of the article on Ultrasonic cleaning. The help article Help:Introduction_to_talk_pages/All suggested that I draw some attention to it, since the article is a bit obscure.

RfC on states at Fermi level is equivalent to metallic conduction (and vica versa)

Are states at Fermi level equivalent to metallic conduction (and vica versa)?

Sandbh is claiming that they are not equivalent, and that similarly the opposite of having no states at the Fermi level is not equivalent to a non-metal (i.e. insulator/semiconductor etc) which does not conduct electricity, creating an edit war. This is in both Nonmetallic materials and Metals. The sources quoted are Ashcroft and Mermin and Kittel, the relevant chapters as (obviously) the Fermi-Dirac statistics and conduction is more complex than one sentence. It seems that Sandbh considers anything that is a paraphrasing as WP:OR, only direct quotes can be used. Unfortunately Sandbh appears to never have had any training in solid state physics. I am posting the RfC here as it covers more than one page and this is the most obvious place for it, particularly in light of his previous question here. Ldm1954 (talk) 14:39, 29 June 2024 (UTC)

Addendum, for simplicity you may want to just vote Equivalent or Not Equivalent with a little justification, similar to WP:AfD. Ldm1954 (talk) 14:41, 29 June 2024 (UTC)

No, I'm not claiming they are not equivalent.

Rather, I'm saying that neither Ashcroft, nor Mermin and Kittel, write what Ldm1954 is including in Nonmetallic materials and Metal. Here are the extracts from the the two articles:

Metal: "These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not."

Nonmetallic materials and Metals: "A nonmetal has a gap in the energy levels of the electrons at the Fermi level."

Neither Ashcroft, nor Mermin and Kittel, refer to nonmetallic materials, or nonmetals in these terms. I've asked Ldm1954 for specific page numbers but he has has not provided any. Both sources do however refer to metals in the terms mentioned in the article, and that is fine. My concern here is not about metals, but rather about nonmetals.

No, I don't consider anything that is a paraphrasing as WP:OR. Paraphrasing occurs widely throughout WP as legitmate form of expression.

What is WP:OR is adding content to articles, whether in quotes or in paraphrased form, that is not explicitly mentioned in those sources. That is what going on here.

As WP:OR states (emphasis added):

"The only way you can show that your edit is not original research is to cite a reliable published source that contains the same material. Even with well-sourced material, if you use it out of context, or to reach or imply a conclusion not directly and explicitly supported by the source, you are engaging in original research; see below.

Yes, I've never have had any training in solid state physics. So I ask lots of questions and do a lot of research.

--- Sandbh (talk) 07:39, 30 June 2024 (UTC)

This explains it

Not sure what you mean by "states at Fermi level", but if the Fermi level is within a band, you have a metal. If it's outside of a band, you have either a semiconductor or an insulator, i.e. a non-metal. See diagram on the right. Headbomb {t · c · p · b} 17:46, 29 June 2024 (UTC)

Thanks. You phrased it slightly differently, but what you say is equivalent to states at E_f and the diagram. I will take this as an Equivalent vote Ldm1954 (talk) 18:17, 29 June 2024 (UTC)

Equivalent, I suppose. I agree with Headbomb that "states at a Fermi level" is...curious phrasing, but certainly if the Fermi level is within an energy band, then it's a metal, and outside of a band, depending on the band gap/position of the Fermi level relative to bands/etc you have a semiconductor or insulator. I believe Simon's Oxford Solid State Physics has a perhaps more succinct and readable section that may be easier to cite to someone who has less background in the field? I will note that the idea of the Fermi level shows up in more areas than just solid state physics so maybe this is part of the origin of the confusion? (Other references that may be useful are Blundell & Blundell, Schroeder's Thermal Physics, etc.) --Nerd1a4i (they/them) (talk) 23:26, 29 June 2024 (UTC)

All (what we call) metals have a nonvanishing density of states at the FL and exhibit so-called metallic conduction. Some materials that are semiconductors in the bulk do have a nonvanishing density of states at their surface and do conduct at 0 K. Some materials with a low density of states near the FL can be brought into a metallic conduction-regime by gating or chemical doping, but the fact does not make them metals in everyday sense. Some materials are gapped at the FL for the "supermobile" fraction of their charges, but the fact does not make them semiconductors at 0 K. All-in-all: it's equivalent, with some caveats for those who want to know more. Ponor (talk) 23:52, 29 June 2024 (UTC)

Extended states are needed for conduction. Xxanthippe (talk) 01:06, 30 June 2024 (UTC).

What is this new interpretation of classical physics?

The article Philosophical interpretation of classical physics discusses the philosophy of classical physics as seen from the perspective of modern physics. However such an article is kind of redundant because it wants to delve into the interpretations of quantum mechanics in order to discuss how the classical physics emerges. It would be preferable to discuss the OLD philosophical interpretation of classical physics but again we already have classical physics and philosophy of physics for that. Delete? ReyHahn (talk) 11:19, 3 July 2024 (UTC)

I am adding a courtesy ping of @Patrick0Moran and @David R. Ingham since it seems from the history that they collaborated on this page 2005-2006. Many things on Wikipedia have changed, and since I think they are both still active their comments would be useful ahead of your suggested AfD. Ldm1954 (talk) 11:50, 3 July 2024 (UTC)

Looks like an essay more than anything else. I'd sent for deletion personally. Headbomb {t · c · p · b} 11:52, 3 July 2024 (UTC)

Delete. There is no evidence in the article of such a topic in the literature of philosophy. Could be a redirect to classical limit. Discussions of Feynman's path integral formulation of QM and similar variational methods sometimes venture into "why does the world seem classical". Johnjbarton (talk) 17:04, 3 July 2024 (UTC)

Given that the only real reference is Messiah's book on quantum mechanics, I think there's no evidence that the topic exists, and therefore it should go straight to AfD. Note that there was an attempt back in 2005. Tercer (talk) 20:03, 3 July 2024 (UTC)

Looks like a typical example of Wikipedia from two decades ago — enthusiasts writing an essay using the thoughts off the top of their heads rather than dredging the philosophy literature for what it says about classical physics. I went ahead and redirected the page to Philosophy of physics because, while I think it might as well be deleted, I also don't believe we need to spend a whole week debating it. XOR'easter (talk) 22:17, 3 July 2024 (UTC)

Thanks. I agree that was the best move.--ReyHahn (talk) 07:56, 4 July 2024 (UTC)

Keep. Nature is quantum. Classical physics is an approximation, but usually an unconscious one, one without which we can't get out of bed in the morning. Schrödinger said in his cat paper that classical physics "cannot do justice to nature", so what is it and why do we need it? Shouldn't we try to explain things in terms of the real physical world, rather than trying to explain a theory in terms of one of its approximations? David R. Ingham (talk) 20:09, 18 July 2024 (UTC)

Delete the new article Quantum science

New article Quantum science which appears to me to be simple WP:SYNTH with no independent merit. However, I don't know all the Quantum pages, so I am checking first before an AfD. Ldm1954 (talk) 12:15, 5 July 2024 (UTC)

"Built on the concept of quarks and on advanced mathematical modeling" yeah no, this isn't a thing. Headbomb {t · c · p · b} 14:02, 5 July 2024 (UTC)

If "quantum science" has any established meaning, it refers to quantum mechanics in a broad sense. Compare with quantum physics. Jähmefyysikko (talk) 14:24, 5 July 2024 (UTC)

The article seems to have puffed up an attempt by a couple of groups to define a new field for applications of QM, building on the success of quantum computing. The article has a couple of references that clearly use "quantum science", an uncited book from 2022 and a Caltech site. Several previously established (quantum biology, quantum chemistry) or wannabe (quantum nanotechnology) fields are folded in as examples. (This is, AFAIK, the process by which new fields get defined in general).

Alternatively you could view "quantum science" as the union of all sciences devoted to quantum mechanics, eg quantum biology, quantum chemistry, quantum physics, and so on. The fundamental flaw in this view is of course that, except for biology, these fields are dominated by QM.

If I could bring out my all-powerful magic wand I would merge quantum science in to quantum engineering, because the latter term seems much clearer and more sensible to me. "Quantum science" will be forever ambiguous with "quantum mechanics"; "quantum engineering" seems to evoke a fresh adventure.

But if we go by references, the quantum science is a legitimate topic even if it is unfamiliar to us as such. The only grounds I see to delete quantum science would be something like WP:TOOSOON. I think a fair representation would include the origin story for the concept but we may not have refs for that.

I will delete some of the egregious and unsourced material in the article so any AfD can focus on the sourced content. Johnjbarton (talk) 16:29, 5 July 2024 (UTC)

Yeah, that page is a whole lot of nothin'. It attempts to synthesize a dictionary entry, but we don't make articles by gathering together a few uses of a term. On top of that, even after a cleanup attempt it reads like nonsense posted to LinkedIn about quantum computing. Junk it — take it to AfD or just redirect it to quantum mechanics, whatever. XOR'easter (talk) 17:42, 5 July 2024 (UTC)

Redirect. Xxanthippe (talk) 23:07, 5 July 2024 (UTC).

Redirected. Headbomb {t · c · p · b} 00:25, 6 July 2024 (UTC)

Seems to me the same logic applies to Quantum technology and Quantum engineering. Johnjbarton (talk) 01:00, 6 July 2024 (UTC)

Agreed, they are all Quantum synthesis/coatracks. There is also Quantum nanoscience. Ldm1954 (talk) 01:22, 6 July 2024 (UTC)

Quantum tech makes sense to me. I'm also not really offended by Quantum engineering, though that's kinda redundant with quantum tech. Quantum nanoscience is fully redundant with nanoscience. Headbomb {t · c · p · b} 03:05, 6 July 2024 (UTC)

I suggest redirecting quantum nanoscience to nanotechnology and merging quantum technology with quantum engineering. The fewer abandoned articles full of LinkedIn/PowerPoint dumps, the better. XOR'easter (talk) 17:57, 6 July 2024 (UTC)

Done the redirect. The merge is more complex so I'll leave that to others. Headbomb {t · c · p · b} 18:33, 6 July 2024 (UTC)

I picked quantum engineering as the merge target and went ahead with a (selective) merge. XOR'easter (talk) 20:12, 6 July 2024 (UTC)

The redirect was reverted without explanation. I don't have the time or energy to deal with this right now. XOR'easter (talk) 00:02, 8 July 2024 (UTC)

I reverted. No explanation was given for the unmerge. Headbomb {t · c · p · b} 00:12, 8 July 2024 (UTC)

Which one was reverted? Whoever did it is allowed to revert, although an explanation would be good. It is probably best to go to AfD or similar if it is contested. I found it. I think it was just an overenthusiastic revert by a newish user who was trying to help fight vandalism; we all make mistakes. Ldm1954 (talk) 02:29, 8 July 2024 (UTC)

Mixing (mathematics) and Mixing (physics) merge proposal

See Talk:Mixing_(mathematics)#Merge_proposal. Please leave comments on that talk page and not here. Mathwriter2718 (talk) 01:15, 9 July 2024 (UTC)

Proposal to merge Rutherford scattering experiments into Rutherford scattering

Please weigh in on this proposal: Talk:Rutherford_scattering#Merge_proposal

ping: @Ajrocke, ReyHahn, and Kurzon: Johnjbarton (talk) 02:20, 16 July 2024 (UTC)

The unopposed merge is complete. Johnjbarton (talk) 23:17, 18 July 2024 (UTC)

Major upgrades to Rutherford scattering experiments and Plum pudding model

@Kurzon and I recently revamped these two articles pretty much top to bottom. Please review. Johnjbarton (talk) 23:19, 18 July 2024 (UTC)

Metal update suggestions please

I have been slowly doing some updates to Metal so it is a bit broader in context. It is a bit of a mush of everything, many parts not well sourced. I would appreciate suggestions at Talk:Metal#Update suggestions welcome, or just be bold and edit. Almost certainly some fluff can go.

N.B., if anyone is a card carrying metallurgist, the alloy section may need some tweaking. Similarly conductive polymers/ceramics. Ldm1954 (talk) 13:53, 19 July 2024 (UTC)

RetractionBot

I posted this story from the Signpost last month. Things have evolved a bit and now Retraction bot handles {{Erratum}}, {{Expression of concern}}, and {{Retracted}}. These populate the following categories:

• Category:Articles citing retracted publications (291)

1. Ball-pen probe
2. High-temperature superconductivity
3. Majorana fermion
4. Superconductivity

• Category:Articles citing publications with expressions of concern (60)

1. No physics-related articles

• Category:Articles citing publications with errata (67)

1. No physics-related articles

If the citation is no longer reliable, then the article needs to be updated, which could be as minor as the removal/replacement of the citation with a reliable one, to rewriting an entire section that was based on flawed premises. If the citation to a retracted paper was intentional, like in the context of a controversy noting that a paper was later retracted, you can replace {{retraction|...}} with {{retraction|...|intentional=yes}}/{{expression of concern|...}} with {{expression of concern|...|intentional=yes}}/{{Erratum|...}} with {{Erratum|...|checked=yes}}.

I put the list of articles within the scope of WP:PHYS in sub-bullets. Feel free to remove/strike through those you've dealt with. Headbomb {t · c · p · b} 02:51, 21 July 2024 (UTC)

Done.--Srleffler (talk) 05:47, 21 July 2024 (UTC)

Coulomb "constant"

As far as I am able to determine, Wikipedia has invented the "Coulomb constant". There is a redirect for the term that points to Coulomb's law. I've changed that page to get rid of the invented term. Just to be sure, I checked sources like J.D. Jackson, R. Feynman, Panofsky and Phillips, and Purcell's Berkeley Physics E&M. They all discuss this factor in Coulomb's law as a proportionality constant or just as a convention for units.

So questions

• Should the redirect Coulomb constant be deleted?
  • I guess no, as I understand this can cause issues with links.
• Should there be something explicit about this non-thing?
  • Maybe add more about the units issue (I can source it per above). But I don't want go down the cgs/rmks rabbit hole.
• Other input?

Johnjbarton (talk) 03:21, 23 July 2024 (UTC)

I did find one source that uses the term:

• Deza, M. M., Deza, E. (2014). Encyclopedia of Distances. Germany: Springer Berlin Heidelberg.

But that source has it under a list of "physical constants" which is just incorrect. Johnjbarton (talk) 03:39, 23 July 2024 (UTC)

It does not seem to be purely a Wikipedia thing: see Ngram, and this this pre-2000 Google Books search which returns few hits. The usage seems rare enough that it does not necessarily need to be named, but giving the name might be the most stable solution, since IPs and other editors users will for sure restore the name from time to time. Jähmefyysikko (talk) 04:06, 23 July 2024 (UTC)

Usage is extremely widespread. High school and university students will encounter $F=k{\frac {q_{1}q_{2}}{r^{2}}}$ well before they see the $F={\frac {1}{4\pi \varepsilon _{0}}}{\frac {q_{1}q_{2}}{r^{2}}}$ version of Coulomb's law, and k is called either the 'electric force constant' or 'Coulomb's constant' in those context. Headbomb {t · c · p · b} 09:00, 23 July 2024 (UTC)

They may see this on the internet along with many other things. I have four authoritative sources which do not use the term "Coulomb's constant". Johnjbarton (talk) 14:52, 23 July 2024 (UTC)

It has several names (electric force constant, electrostatic constant, Coulomb force constant, ...). Here's about 4000 books that call k the Coulomb constant.

More advanced texts like Jackson prefer to work with closer-to-the-metal concepts, and use ${\frac {1}{4\pi \varepsilon _{0}}}$ instead of k and just don't need a name for that specific clump of variables. Headbomb {t · c · p · b} 18:10, 23 July 2024 (UTC)

Ok sorry I missed this post. I see there are plenty of other refs. Johnjbarton (talk) 03:46, 24 July 2024 (UTC)

@Jähmefyysikko Of course you can find it on the internet. But I was looking at reliable sources. Why would me make an exception for this case? Johnjbarton (talk) 14:54, 23 July 2024 (UTC)

No, nothing was invented there. That's how they teach the law in primary and secondary ed (at least in some countries). It's the analog of the gravitational constant, and how you express the qQ and 1/d² law without knowing the full theory of electromagnetism.

Britannica has it

Ponor (talk) 07:42, 23 July 2024 (UTC)

As for the constant name itself (in English alone):

[1] [2] [3] [4] etc. Ponor (talk) 08:03, 23 July 2024 (UTC)

I've restored mention that this is called the Coulomb constant. This is absolutely critical information to mention. Headbomb {t · c · p · b} 08:45, 23 July 2024 (UTC)

@Ponor Thanks, but these are all web sites, unreviewed and not authoritative sources. Johnjbarton (talk) 14:48, 23 July 2024 (UTC)

@Johnjbarton: I'm saying the redirect should not be deleted because the name is already out there and people will search for it. I did find the sentence "where k_e is a constant called the Coulomb constant" in my Serway and Jewett: Physics For Scientists and Engineers 6th ed, p 711 + pp 720, 728, Index, and table of "Some physical constants". I do not have any high school books in English. As for Britannica: at first I though you were disputing any use of k_e (as I saw some diffs for Coulomb law), my mistake! Ponor (talk) 15:27, 23 July 2024 (UTC)

I put the ninth Edition of Serway as a reference in the article. Standard 1000-level university textbook. Headbomb {t · c · p · b} 18:12, 23 July 2024 (UTC)

@Ponor Thanks. Please read the Britannia source carefully. It never says "Coulomb's constant". It says the same thing as my sources:

• "Expressed in the form of an equation, this relation, called Coulomb’s law, may be written by including the proportionality factor k as F = kq1q2/r2."

Johnjbarton (talk) 14:50, 23 July 2024 (UTC)

Surely this is a case where there is ambiguity, so the WP:NPOV is to be inclusive. I suggest that where k is mentioned we add "The proportionity constant k is sometimes called the Coulomb constant.[ref]" Perhaps even add an anchor and have the redirect go to the anchor. Ldm1954 (talk) 19:05, 23 July 2024 (UTC)

This is not ambiguous. There are other names, like the electric force constant, or Coulomb force constant, but if you ask any physicist what's the Coulomb constant, they'll all say ~8.99×10⁹ N.m²/C² Headbomb {t · c · p · b} 20:07, 23 July 2024 (UTC)

I have no vested interest in any of these names, but I do feel that we should be inclusive as encyclopedia editors. While I agree with your statement about "ask any physicist", we are writing for everyone, and in my opinion should try very hard to be discipline neutral. The fact that there is some debate here suggests to me that it is worth mentioning the other names -- what is an extra sentence between friends? Ldm1954 (talk) 21:07, 23 July 2024 (UTC)

@Headbomb Well that's the thing. I "asked" Feynman, Panofsky and Phillips, Purcell, and JS Jackson. They all agreed: Coulomb's law does not need a "Coulomb's constant". I tried The NIST site. I checked the Particle Data Group Physical Constants (a major revision). Zip.

We all form our opinions based on our experiences. You must have run in to textbooks that used the name, but this use is clearly far from standard or universal. Personally I had never seen or at least noted the symbol $k_{e}$ before a couple of weeks ago and never heard of thing called "Coulomb's constant". In my experience $k$ just stands for what ever constants are needed by the units in whatever formula is being discussed.

We have references that use this term and many notable ones that could, but do not. In my opinion this dichotomy should be discussed in the article. I will go ahead and make some changes and hopefully we can agree on some middle ground matching the sources. Johnjbarton (talk) 01:15, 24 July 2024 (UTC)

Coulomb's law does not need a "Coulomb's constant". Sure, in the same sense that you don't "need" Rydberg's constant, you have ${\frac {m_{\text{e}}e^{4}}{8\varepsilon _{0}^{2}h^{3}c}}$. You don't "need" the Bohr magneton, you have ${\frac {e\hbar }{2m_{\mathrm {e} }}}$. You don't need the Bohr radius, you have ${\frac {4\pi \varepsilon _{0}\hbar ^{2}}{e^{2}m_{\text{e}}}}$.

Headbomb {t · c · p · b} 01:34, 24 July 2024 (UTC)

Sorry, but your examples only provide additional evidence for my point of view.

The term "Rydberg's constant" appears in A. Pais book "Inward Bound" and Whittaker's Aether and Electricity history; it appears on the CODATA site. Similarly for the Bohr magneton. I'm sure I could find many more refs for these terms, these just happened to be on my desk today.

It is exactly this difference in the level of extensive, reliable sources that make these terms notable enough for a complete article. My same broad sources are mute on "Coulomb constant." This difference should be part of our article per WP:NPOV. Johnjbarton (talk) 02:18, 24 July 2024 (UTC)

I've linked to roughly 4000 books that call it the Coulomb constant. If you want one specifically, there's Serway. This is a standard 1000 level intro to EM university textbook. This is not WP:NPOV, this is basic physics terminology. Headbomb {t · c · p · b} 02:25, 24 July 2024 (UTC)

Reliable sources for the term have been presented. That is sufficient. The fact that some other sources happen not to mention it is irrelevant to the question of whether we should. --Srleffler (talk) 06:51, 28 July 2024 (UTC)

@Srleffler I guess you missed my post above the same way I missed @Headbomb's post with the refs earlier in the topic. Johnjbarton (talk) 23:50, 28 July 2024 (UTC)

Rumford Medal nominated as featured list

Hello everyone. I have nominated this article for Featured List status (review page here). If possible, please share your feedback on the review page. Any input is appreciated. Nitro Absynthe (talk) 08:19, 23 July 2024 (UTC)

RfC: On discovery of the 23 nonmetals

Should this content on the discovery of the 23 nonmetals be removed from the nonmetal article?

RfC is here. --- Sandbh (talk) 13:39, 23 July 2024 (UTC) (He did not post here, but I am since it is maybe relevant given the prior discussion #What is a nonmetal (in physics)?.) Ldm1954 (talk) 22:34, 24 July 2024 (UTC)

Request for comment: presenting Rutherford's 1911 paper in Rutherford's way.

Please offer your opinion on this topic at Request_for_comment:_presenting_Rutherford's_1911_paper_in_Rutherford's_way. Thanks Johnjbarton (talk) 22:32, 28 July 2024 (UTC)