Wikipedia:Articles for deletion/Free-fall atomic model


 * The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review).  No further edits should be made to this page.

The result was delete. This is a topic for and by specialists. At first glance no consensus emerges here. But I'm inclined to defer to the unanimous "delete" view of established editors with a track record of constructive contributions in the topic area. And I give less weight to a "keep" side represented entirely by IPs and low-editcount accounts, because with these contributors, canvassing, sockpuppetry or COI is a frequent concern.  Sandstein  09:05, 11 October 2016 (UTC)

Free-fall atomic model

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This is, I think, a very obscure theory, and as far as I can tell, one that never really made an impact. All citations are from Gryziński, who proposed this, and AFAICT aren't cited by much anyone except Gryziński himself. I'm open to be convinced that the article should be kept, but as of now I just don't see how this meets WP:N. I don't have access to a lot of those articles however, so I don't have access their full citation record. Headbomb {talk / contribs / physics / books} 15:06, 26 August 2016 (UTC)
 * These are 20+ papers from the best journals, some have huge amount of citations - according to Google Schoolar: "Classical Theory of Electronic and Ionic Inelastic Collisions" - 446 citations, "Two-particle collisions. I. General relations for collisions in the laboratory system" - 559 citations, "Two-particle collisions. II. Coulomb collisions in the laboratory system of coordinates" - 324 citations, "Classical Theory of Atomic Collisions. I. Theory of Inelastic Collisions" - 1308 citations 91.198.177.113 (talk) 15:27, 26 August 2016 (UTC)


 * Yes, but those aren't about the free fall model, just collisions in general. Headbomb {talk / contribs / physics / books} 16:06, 26 August 2016 (UTC)


 * These are respected results from purely classical considerations - including electrons, leading to surprisingly good agreement. And so the author has later also seen atoms in a classical way - with electrons falling to nucleus, then returning to the initial distance, like zero angular momentum degeneration of Bohr-Sommerfeld. This falling and drifting away makes atom effectively a pulsating multipole - such picture was used in his later classical scattering models. Anyway, shouldn't Wikipedia notice that trials of classical treatment of atom has not ended with Bohr-Sommerfeld? Gryzinski is definitely the most notable among such approaches. Classical approximation is useful for semi-classical ones. His main coauthor is professor Joseph Kunc ( https://gapp.usc.edu/about/faculty/joseph-kunc ) 83.12.37.198 (talk) 16:59, 26 August 2016 (UTC)
 * Gryzinski has worked in group of hot plasma for nearly half a century (article in Polish: http://web.archive.org/web/20121031093355/http://www.paa.gov.pl/dokumenty/ptj/sadowski10.pdf ), they have stated approach to fusion which is now called Dense plasma focus, he was the head of this group for 18 years. In this energy region classical approximations were sufficient. Now semi-classical approximations are popular, Rydberg atoms are often seen nearly classical. There should be some article about modern classical approximations. — Preceding unsigned comment added by 188.146.128.48 (talk) 22:03, 26 August 2016 (UTC)


 * Comment Although I am uncomfortable with all references being a single author who produced a seemingly large body of work on this subject, doesn't' the fact that these are all published in peer reviewed journals carry some weight toward notablity? Also, these are top tier physics journals and the journal Nature. I don't see how anyone can do better than that - other than garner citations from other physicists. Maybe I am looking at this incorrectly, but I am tending toward " Keep ". Headbomb, what is your opinion on what I just wrote? Steve Quinn (talk) 18:00, 27 August 2016 (UTC)


 * The majority of those citations are not related to the FFAM, but are rather general articles about the physics of particle collisions and the like. Yes they are good articles, but they don't support the material, so my opinion is unchanged because the citation that ARE related to the FFAM are very low impact, and very few people other than Gryziński ever bothered with his model. Headbomb {talk / contribs / physics / books} 18:38, 27 August 2016 (UTC)
 * All of these papers are about classical considerations, including treatment of electron, which is usually a part of an atom there. The topics of classical scattering and FFAM are integrally connected/interleaved: 1) scattering was used to infer and experimentally test these models (often personally by the author), 2) electron in FFAM performs successive scatterings from the nucleus, 3) atoms in FFAM picture are effectively pulsating electric multipoles (dipole, quadrupole) what is the base of his later scattering papers (since 1975). These impressive 25+ papers nicely show 43 years of evolution of view of a person who was plasma experimentalist and theoretician: from corrections to scattering models, through including magnetic dipole moment of electron into classical considerations, introducing and testing classical atomic model with better agreement than Bohr's, up to a similar view on multielectron atoms and molecules. Sure these are just approximations, but their surprisingly good agreement with experiments may bring valuable intuitions, helpful e.g. for construction of semi-classical models. 188.146.69.8 (talk) 19:03, 27 August 2016 (UTC)
 * thanks very much. I see what you are saying. This clears things up. Steve Quinn (talk) 21:47, 27 August 2016 (UTC)
 * I have added (a sketch of?) History section (Free-fall_atomic_model) to emphasize integrity of this series of papers - if it helps, I could improve it. Otherwise, feel free to remove it. 188.146.69.234 (talk) 14:05, 28 August 2016 (UTC)
 * IMO, It adds very little because that series of paper is by far an large not about the FFAM, but rather particle collisions in general. Headbomb {talk / contribs / physics / books} 14:27, 28 August 2016 (UTC)
 * These collision/scattering models assume classical electron, and often a classical model of atom - tested by agreement with experimental scattering. For example "Three-body analysis of electron-hydrogen atom collisions": assume a classical model of hydrogen (circular or radial), shoot it with a classical electron, and compare predictions of both with experiment. Or "Ramsauer Effect as a Result of the Dynamic Structure of the Atomic Shell" and "Classical theory of atomic collisions. II. Low energy scattering" see atom effectively as a pulsating multipole, as a consequence of assuming radial electron trajectories. Or "Systematics of spectral lines and classical atom": "It is shown that line intensities and main energy level shifts are directly related to the non-spherical and time-dependent electric field of the atomic core.". 188.146.37.99 (talk) 14:57, 28 August 2016 (UTC)


 * For example alongside the 1965 paper with 1300 citations, he publishes Phys. Rev. Lett. paper.: "Radially Oscillating Electron-the Basis of the Classical Model of the Atom” explaining why assumptions made in the classical scattering paper exclude Bohr circular orbits - here are its first three paragraphs:
 * “In a series of papers on the classical theory of atomic collisions recently published by the author, it has proved necessary, both for the qualitative explanation of a number of experimental phenomena as well as for their appropriate quantitative description, to proceed with certain assumptions which are in contradiction with the prevailing classical notions regarding the structure of atom and, of course, in contradiction with the wave approach to the atom.


 * First, in order to explain such phenomena as the asymptotic form of excitation and ionization formulas for high energies of the bombarding particles and the absence of a threshold for processes of inelastic collisions with heavy particles, it was necessary to assume a continuous velocity distribution of atomic electrons. Second, in order to account the diffraction pattern associated with the crystalline structures, it was necessary to accept the existence of a strong anisotropy in the velocity distribution of atomic electrons.


 * Such assumptions are totally unacceptable from the point of view of electrons moving in circular or even elliptic orbits, since the range of variability of electron velocity is too narrow and the anisotropy too low. The assumption concerning the continuous velocity distribution of atomic electrons may be accounted for on the basis of classical mechanics only by the fact that the moving electron exists both beyond and in the immediate vicinity of the attracting center represented by the nucleus” 188.146.72.198 (talk) 18:47, 28 August 2016 (UTC)


 * Again, that's about the well-known failures of the Bohr model, not about the FFAM. While it certainly may have been a motivation for it, it's still not a paper about the FFAM, and does not succeed in establishing its notability. Headbomb {talk / contribs / physics / books} 13:11, 29 August 2016 (UTC)
 * Just look at the title of this paper: "Radially Oscillating Electron-the Basis of the Classical Model of the Atom”. Radially means along the radius, what is equivalent with free-fall, the third equivalent description used is zero angular momentum. Other close formulations used are just classical regarding electrons, and from first principles (just Newton+Coulomb+Lorentz, without assuming axioms of QM). Let us look at abstract of some later papers: "Collisional ionisation and the atomic model" 29 citations: "...The theoretical results appear to be sensitive to the atomic model used; in the case of the free-fall atomic model, they are found to be in good agreement with the experimental data. ", "“Free-fall” solution of the Kepler problem in the presence of the magnetic moment" 27 citations, it's in title, "A concept of “free-fall” multi-electron atomic model" 24 citations, in title, "Three-body analysis of electron-hydrogen atom collisions" (22 citations): "...The basic feature of the model atom employed in the present work is its zero angular momentum due to the assumption of the radial motion of the atomic electron ('free-fall' trajectory)...". Sure, maybe the list of articles is too long - please point the least connected one. 188.146.146.81 (talk) 13:39, 29 August 2016 (UTC)

Note: This debate has been included in the list of Science-related deletion discussions. Coolabahapple (talk) 09:08, 28 August 2016 (UTC)  Relisted to generate a more thorough discussion and clearer consensus.

Please add new comments below this notice. Thanks,  Sandstein   07:12, 3 September 2016 (UTC)
 * Keep There is 25+ articles from top journals (Phys. Rev. class) with ~ 3000 total citations: https://scholar.google.pl/scholar?hl=en&q=gryzinski . The author was physicist (experimentalist and theoretician) working nearly half a century in Polish Academy of Sciences. The articles consistently cover classical treatment of atoms, including electrons, focusing on agreement with experimental data - much more citations have the classical scattering papers (~2500 total), but direct consequence of their assumptions was the FFAM (1965 Phys. Rev. Lett. "Radially Oscillating Electron-the Basis of the Classical Model of the Atom” article), later tested and used for classical scattering considerations (sensitive to assumed electron trajectory) and other phenomena like Ramsauer effect (1970 Phys. Ref. Lett. "Ramsauer Effect as a Result of the Dynamic Structure of the Atomic Shell"), diamagnetism (1987 Journal of Magnetism and Magnetic Materials "Diamagnetism of matter and structure of the atom") or modeling molecular bond (1994 Chemical Physics Letters "Dynamical model of the molecular bond"). The later articles directly applying FFAM also have total of a few hundreds of citations. 188.146.3.91 (talk) 08:14, 3 September 2016 (UTC)
 * Some of what is written in the above Ivote pertains to off-topic material and also ignores the lack of impact this theory has had in mainstream physics. All of the above, and many article references are meant to artificially puff up the importance of this theory. Wikipedia is not a platform for promoting obscure theories (see Ivote below). Steve Quinn (talk) 21:43, 4 September 2016 (UTC)
 * These 25+ articles have been accepted in top journals - do you imply that editors and reviewers of these journals accept obscure theories? The article emphasizes "This model has never been part of mainstream physics.", but it has both coverage and was not ignored. I responded with concrete arguments from the materials in discussion, please also give concrete objective arguments, not just your subjective evaluation. If you find something "obscure" in these articles, please point it, explain your evaluation and we can discuss your arguments. 188.146.133.196 (talk) 22:20, 4 September 2016 (UTC)


 * Delete This theory has never had a significant impact in the mainstream physics field as demonstrated by the lack of citations by other researchers. It seems to have been ignored. As noted above, most of the article references do not pertain to this particular topic. This theory has not received significant coverage in reliable sources that are independent of the subject per WP:GNG - including the mainstream press. Wikipedia is not a platform for promoting obscure theories per WP:NOTEVERYTHING, WP:NOTFORUM. Steve Quinn (talk) 21:30, 4 September 2016 (UTC)
 * Not significant coverage? Lack of citations by other researchers? Here you have access to a list of ~3000 citations for 25+ articles from top journals: https://scholar.google.pl/scholar?hl=en&q=gryzinski . Here you have example of Wikipedia article for 1 paper with 13 citations: Statistical Lempel–Ziv. Where is the boundary? 188.146.64.200 (talk) 22:00, 4 September 2016 (UTC)
 * How about if you stop with the misleading POV assertions. Steve Quinn (talk) 04:43, 6 September 2016 (UTC)
 * Before questioning someones objectivity, please finally start with a single objective argument - based on the given historical material. This deletion nomination and discussion currently looks like a witch hunt, far from being objective. The official reason is lack of notability, but if measured in papers and citations, it easily exceeds tenfold notability of many other Wikipedia articles. The only other given reason is being “a very obscure theory” without providing even a single argument for this very subjective evaluation. I have looked closer at some of these papers (I have PhD in physics) and they contain solid calculations (wouldn’t be accepted in these journals otherwise) using just basic classical physics, like Coulomb and Lorentz force, and compare their theoretical predictions with experimental values, getting surprisingly good agreement – please explain what is controversial or obscure here? If you have found some weaknesses of their analysis, missed by the reviewers, please share it. They obviously lack the perfection of quantum predictions, but it is definitely good to know the limits of classical considerations, especially that the discussion about the foundations of quantum mechanics still continues. If your objection is lack of connections between these 25+ papers, there was a specific question above to point the least connected paper - still zero answers. Please respond to the evidence above, which refer to the actual text showing their connection - like the 1965 Phys. Rev. Lett. paper explaining necessity of FFAM electron trajectory for the 1300 citations classical scattering paper. 188.146.144.42 (talk) 08:29, 6 September 2016 (UTC)


 * Comment - this short article might be interesting for the history of physics, but it seems to be relegated, no? Bearian (talk) 18:47, 12 September 2016 (UTC)
 * There is a nice 2012 Grujic "Classical theory of atomic collisions – The ﬁrst hundred years" review, which discusses two schools: semi-classical "Stirling school" and classical "Warsaw school" (Gryzinski's), with nice comment to his classical atomic models: "(...) may be considered a historiographical alternative, which answers the possible question: what would have happened had the QM not been invented?". The number of citations itself suggests theses papers had a real influence on the history of physics. However, these had finally turned out to be an alternative history - very solid work to understand how far can we go with the classical approximation. Understanding its limitation - what is still missing, is one of a natural way to really deeply understand the quantum mechanics. 188.146.68.213 (talk) 21:16, 12 September 2016 (UTC)

 Relisted to generate a more thorough discussion and clearer consensus.

Please add new comments below this notice. Thanks,  Sandstein   18:11, 13 September 2016 (UTC)


 * Comment The topic in general looks relevant, but I'm not sure if the current article is sufficient to give an overview: what are the applications of the model, what are the limits? Is this purely of historical interest, or still relevant? As an example, if the model is unable to reproduce quantized energy levels, this should be mentioned (because it means the model is not useful for atoms at all). If it is, this is a remarkable achievement for a classical theory and should be mentioned. If the atom has a time-dependent dipole, why doesn't it radiate? --mfb (talk) 18:53, 13 September 2016 (UTC)
 * Applications started with various scattering scenarios, later he has also used it for different topics like Ramsauer effect (as higher state electrons screening the lower ones), calculating diamagnetic coefficient, Stark effect and a few others. Limits? These are pure classical (e.g. no interference) - Bohr plus magnetic dipole moment of electron, plus precession of this spin (also as gyroscope), he has used this precession to explain Bohr-Sommerfeld quantization (1987 "Spin-dynamical theory of the wave-corpuscular duality"). This quantization basically produces energy levels as Bohr. Regarding lack or bremsstrahlung, I don't know his explanation. Personally, I see it through Couder's quantization for walking droplets ( http://www.pnas.org/content/107/41/17515.full ): closed trajectories and Bohr-Sommerfeld condition lead to resonance with the surrounding field. 89.70.181.191 (talk) 20:34, 13 September 2016 (UTC)


 * Delete. The banner question for content like this is simple: is there independent reliable coverage? That is, did other people directly address them at nontrivial length? The IP editor supporting retention has provided a lot of links to scholarly discussions of particle collision physics in the general case, and a lot of citation counts for Gryziński's works. But neither of those approaches illuminate whether this model is itself notable. For example, a couple of Gryziński's flagship papers that directly address this theory are in Physics Letters A: "A concept of 'free-fall' multi-electron atomic model" and "'Free-fall' solution of the Kepler problem in the presence of the magnetic moment", each with a couple dozen citations. However, the bulk of those are self-citations from Gryziński's other papers, and none of the independent citations seem to give significant coverage of the topic. Indeed, papers like this Physics Reports article look promising, but are primarily concerned with his 1959 work, which predates the free-fall model. Honestly, I think the best solution here would be to redirect this article (merging appropriately given due weight) to an article on Gryziński himself; he's done some fairly significant things and, overall, has been pretty well-cited, and I think there's a case that he's notable. But currently, Michał Gryziński redirects to this article. In the absence of a viable redirect target, and given the lack of independent reliable coverage of this model specifically, I can only support deletion. Squeamish Ossifrage (talk) 18:20, 23 September 2016 (UTC)
 * Lots of people have been working on classical considerations in this scale even after QM, and Gryzinski's half century of tremendous work is definitely the most notable among them: based on agreement with many different experiments, published dozens of papers about it in top journals, got thousands of citations. An ultimate argument against Bohr's picture, which is taught in schools, is electron capture - which requires electrons to get to femtometer scale distance so nuclear force can start acting (as in FFAM). The FFAM has been the base of his papers since the PRL in 1965, which introduced it as requirement for his classical scattering papers with 2000+ citations. These later 20+ papers have about 500 total citations - if it is not sufficient for a separate Wikipedia article, change it to Michał Gryziński, modify the order (FFAM after History, I can help), and redirect from FFAM. Also, there should be a section about his classical scattering papers. 21:14, 23 September 2016 (UTC) — Preceding unsigned comment added by 188.146.64.242 (talk)


 * Keep: This is an alternative theoretical formulation which is tested experimentally in scattering experiments. It is not the only alternative theoretical formulation present on Wikipedia, there are many others like, for instance, non-standard cosmology, so the argument re mainstream belonging does not really hold.--213.233.84.3 (talk) 22:00, 28 September 2016 (UTC)


 * Keep as work in progress towards a more comprehensive article on Gryziński's work or himself. Or possibly move to Draft space if that is ever done.-- pretty IittIe Iiar 04:30, 3 October 2016 (UTC)


 * The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.