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Two edits in
Special:Diff/1167517849/1167516509 removed use of the citation {{
r|padavic-c-20230726}}
(causing a syntax error) and introduced new wording at odds with
MOS:CLAIMED in the Wikipedia Manual of Style. These have been temporary reverted in
Special:Diff/1167521503. (Would encourage
Osunpokeh to attempt their edits again in a way that do not break the page or introduce problematic wording.) —
Sladen (
talk) 07:31, 28 July 2023 (UTC)
Reflecting on articles about various miracle-cure physics and science articles: we could use a style for tagging / talking about claimed advances that deviate dramatically from existing models, with limited intervening discoveries or confirmed theoretical underpinning. <longer style rant + comments moved to User:Sj/miracles> – SJ + 09:17, 1 August 2023 (UTC)
2607: above suggested we would know soon whether this has "panned out or not". This may be true if there are a series of positive results. But if there are only negative results, this is unlikely, as negative claims are hard to prove. Some of the developments that might be expected even if results are negative for weeks:
Inconclusive support
Inconclusive disconfirmation
– SJ + 20:53, 29 July 2023 (UTC)
Related comment by Sabine Hossenfelder - Wild guess: the first reproduction attempts will find the material isn't sc, there will be some discussion about whether the stuff was synthesized correctly, then we'll never hear about it again.
Right now we have three partial success entries in the replication table. All have shown video of a tiny and thin flake, which is perhaps 100x lighter than the object shown w/ partial levitation in the initial paper. Pablogelo has glossed them as 'Preliminary results unavailable' and not 'partial success' which seems right, since this is a minimal result, with no data shared beyond grainy video. (Also: all labs tried to produce much larger quantity than those flakes, so there is likely be a reason they're all showing such tiny pieces through a magnifying glass; we should assume that larger fragments don't show this property. Also, none have showed their flakes alongside flakes of known diamagnets like graphite for comparing strength of interaction.) – SJ + 17:08, 1 August 2023 (UTC)
Removed two lines from the article (no information on the researcher, lab, or any followup; minimal detail in videos). Please add any other questionable replication reports here; we can check on them to see if they have published anything more serious. See also this Wordpress and this forum thread for sporadically-updated lists. – SJ + 17:29, 1 August 2023 (UTC)
Any reported replication efforts with no results, or with teaser images/videos but no results, can go here. They can be moved back if/when they publish.
As the number of published experiments grows, the article should probably just summarize the most notable, but we can keep track of the longer list of verifiable experiments by notable people/labs here or on a subpage. – SJ + 09:21, 3 August 2023 (UTC)
Should [ these] guys be included too. Worcester Polytechnic Institute in Worcester MA in the US. Ittiz ( talk) 13:17, 4 August 2023 (UTC)
Group | Country | Status | Result | Notes |
---|---|---|---|---|
Shanghai University | ![]() |
Unpublished | Synthesized LK-99 powder, saw no diamagnetism. | News report: on-site interview by reporter
[1]
Not Included: unpublished, limited media coverage, very simple contribution. |
Qufu Normal University | ![]() |
Unpublished | LK-99 sample had non-zero resistance. | Press coverage:
[2]
Not Included: ? |
AGH University of Krakow | ![]() |
Unpublished | Images showing partial levitation of a small sample in response to magnetic field. No significant electrical conductivity observed. | Photographs shared on Twitter:
[3]
Team including Prof. Konrad Szaciłowski and Dr. Agnieszka Podborska at AGH University of Krakow. [4] Media Coverage: [5] Not Included: unpublished, limited media coverage, no major contribution. |
Lebedev Physics Institute | ![]() |
Unpublished | Structure confirmed with X-ray diffraction. No diamagnetism was observed. High resistance observed with 4-point probes method. Resistance increases when temperature decreases. | Statement by Lebedev Physics Institute:
[6]
Not Included: unpublished, limited-reliability media coverage. |
National Taiwan University | ![]() |
Unpublished | Diamagnetism observed. Non-zero resistance, no superconductivity. | Li-min, et al.
Press coverage: [11] Not Included: unpublished, limited media coverage, no major contribution. |
University of Wollongong | ![]() |
Unknown | — | Dr. Xiaolin Wang et al.
[12]
Not Included: No results / lacks media reporting. |
Faculty of Mathematics and Physics, Charles University (Prague) | ![]() |
Started on 2023-08-03 | A false mixture of copper and phosphorus in the ratio of 1:3 instead of 3:1 lead to an unsuccessful synthesis. A new attempt is ongoing. | Department of Condensed Matter Physics
[13]
Not included: Lacks media reporting. |
University of Science and Technology of China | ![]() |
Results unavailable | 8/1: Video showing diamagnetism of small sample. | Video uploaded to
Zhihu.
[14]
better source needed
Not included: Lacks media reporting. |
Iris Alexandra [a 1] & Moscow Engineering Physics Institute | ![]() |
Unpublished | Photograph of small sample levitating in glass tube. | Sample synthesis and photograph by pseudonym Iris Alexandra.
[15] Posting on
Twitter. Claimed by this account to have analysis by
Moscow Engineering Physics Institute.
[16]
Not included: No confirmation from media of link with institute. |
Wuhan University of Science and Technology | ![]() |
Unpublished | Very brief video of levitation of sample, allegedly showcasing flux pinning. |
[19]
[20]
Claimed to have been produced by Zhang Xiang at Wuhan University; not confirmed by Xiang or the university; no further context or details. Not included: Lacks media reporting. |
Queensland University of Technology | ![]() |
Unpublished | Not Reported |
[21]
Not included: No results / lacks media reporting. |
Theoretical studies | ||||
Institute of Mathematical Sciences, Chennai and IIT Madras | ![]() |
Preliminary | Theorises a mechanism for superconductivity involving copper chains in LK-99. | arXiv:
G. Baskaran
[22]
Not included: No results / lacks media reporting. |
KAIST and Johns Hopkins | ![]() ![]() |
Preliminary | DFT Analysis of a two-orbital Hubbard model, concluding it would not exhibit superconductivity, but not ruling out other Cu dopings. | arXiv: Oh & Zhang
[23]
Not included: No results / lacks media reporting. |
University of California, Irvine and University of Toronto | ![]() ![]() |
Preliminary | Proposed a minimal tight-binding model which reproduces the main features of the flat bands in LK-99. | arXiv: Omid Tavakol & Thomas Scaffidi
[24]
Not included: No results / lacks media reporting. |
Confusing graph in isolation. There's no clear dropoff, no clear T_c, and a lot of noise at low resistance. While superconducting measurements regularly go down to 1e-7 Ohms, here noise dominates at 1e-5 Ohms. They mention in the preprint the artefact around 230-250K could be sensor error. We should caption carefully.
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Let's use this section to discuss reliability of specific sources.
A tweet, facebook, bilibi, youtube isn't a reliable source and should be avoided when updating this article, multiple users are forgetting it when editing the section on replications, please refer to: /info/en/?search=Wikipedia:Reliable_sources I would suggest a mod to watch that section more thoroughly and a clean-up is needed — Preceding unsigned comment added by Pablogelo ( talk • contribs) 17:10, 1 August 2023 (UTC)
+1. In terms of usefulness as a primary source (a clear record of what a verifiable person did, as plausibly claimed by them + not just attributed to them), I would say
And our biggest challenge currently is we need more unambiguous papers. – SJ + 17:52, 2 August 2023 (UTC)
According to the claims of this post on YCombinator, LK-99 may not be a superconductor "in a traditional sense". To quote, "it should be first noted that this substance is not a strict superconductor in the current theory." It is said to be engineered with certain tradeoffs, removing properties typically associated with superconductors (e.g. Meissner effect) to enable operation at room temperature. Thus it would be less likely to be classified as a superconductor, even if it did conduct current with zero resistance. The post received "substantial updates" since its initial release, which fixed "possible misreadings and inaccuracies".
The speculation that specifically caught my attention was "This whole discourse should make you more careful to conclude whether LK-99 is a superconductor or not, because we may well end up with a revised definition of SC as a result." This may or may not be notable, but I thought the source was worth surfacing if not done so already.
https://news.ycombinator.com/item?id=36996337 — Preceding unsigned comment added by 68.10.151.165 ( talk) 03:56, 5 August 2023 (UTC)
different phrases have the same color while the same phrase also has a different color, I guess the color is based on outcome but wouldn't it be smarter then to color the "Result" Column? Littlerootlodge ( talk) 08:39, 2 August 2023 (UTC)
This seems fine. But: is the current color-setup automatically generated by the template? – SJ + 02:31, 3 August 2023 (UTC)
Partial success and partial failure are basically the same color and it's driving me crazy. Is there no respect for the color blind? There's gotta be a better way to color code this stuff. DontLikeRedesign ( talk) 12:16, 8 August 2023 (UTC)
These tables should be concise overviews to inform the article, not hat racks for any unreviewed preprints or claims that emerge. It so happens that some of the very early analyses were from highly notable labs. But in general these tables should be a selection of the most relevant work at any point in time. My take:
The tables should also be more concise: perhaps we can drop the References column; refs should be inline with claims, wherever possible, and the rest can be attached to a "Media mentions:" line at the end of publication status. – SJ + 11:56, 3 August 2023 (UTC)
The mechanism section needs work, and should be shorter. While some theories have been proposed, none is known; and in the absence of observed sc it's hard to describe a potential mechanism for a potential observation w/o implying the observation has occurred. – SJ + 08:33, 8 August 2023 (UTC)
I removed the following section, as it's synth from old papers. The article should only contain summaries of mechanisms that are clearly described by secondary sources, or in quotes from interviews, or proposed specifically for this material (e.g., a new paper on "mechanism for LK-99 levitation", like the ferromagnetic half-levitation paper). – SJ + 08:56, 8 August 2023 (UTC)
- Proposed mechanism for diamagnetism
Although the Meissner effect cannot be seen in one-dimensional superconductors, Hyun-Tak Kim claims that a sample of LK-99 shows a strong diamagnetism of 5450 times that of graphite, despite its low purity, although no Meissner effect was observed. A suggestion is that the measured three-dimensional LK-99 sample has a polycrystal structure which may result in appearance of both superconductive and diamagnetism. Chair also pointed out that single crystals and composites can have very different properties.
Currently, the section is misleading QCentre supports both SQW and and BR-BCS while it . In fact, SQW is Kwon's theory(sukbae-2023). Unfortunately, QCentre already stated they requested to discard the paper and they disagree to publish the paper. BR-BCS is Hyun-tak Kim's theory. Hyun-tak Kim wrote(ref: SBS interview) the paper(sukbae-2023-2) referring BR-BCS theory which QCentre team agreed. Their original theory is none of them. It was electron superfluid(sukbae-2023b). It is removed since https://en.wikipedia.org/?title=LK-99&diff=1169305425&oldid=1169304194. Since Hyun-tak Kim already finished LK-99 with BR-BCS in 2022(interview), both sukbae-2023b and sukbae-2023-2 are QCentre's official papers with different view with or without Hyuntak's theory. Since only Hyun-tak take interviews while Sukbae doesn't, confirming QCentre still keeps their original theory in sukbae-2023b will be hard at the moment. But confirming QCentre replaced sukbae-2023-2 with sukbae-2023b will be also impossible. At least the superfluid theory looks more important than SQW by citating QCentre.
The mechanism is complex and much more work is warranted as we can see from prior work in this area which was established through extensive theory connected with metrology. Adding relevant references from Rev.Mod.Phys to give the context is warranted. -- QuantumJIM1994 ( talk) 21:11, 8 August 2023 (UTC)
The prior brevity of this section which only cited a single arxiv paper from LBNL is too short. It risks making that single paper as the sole source (which can still be incorrect) The replication by other groups is relevant within the context of the LK99 research being new and fast changing. Also to note are the additional insights provided in the references. Citations to critical work listing the gaps should not be deleted to allow readers to have knowledge of the required future work. -- QuantumJIM1994 ( talk) 21:11, 8 August 2023 (UTC)
Youknowone ( talk) 12:44, 8 August 2023 (UTC)
This patent [2] related to LK-99 mentions another patent [3] filed by Salvatore Pais. Apart from these WP:PRIMARY sources there seems to be no WP:RS connecting Pais to this article.
As such I have to ask: Is it really helpful to simply place a link to Pais in the "See also" section ?
I think not. Lklundin ( talk) 18:02, 8 August 2023 (UTC)
On the page for that guy it links back here to LK-99 - this to me looks like link farming. 94.14.250.118 ( talk) 18:22, 8 August 2023 (UTC)
Now we finally got serious people working on the topic: [4]. They characterized the samples and do not see any superconductivity. Not including this to the article because there was no media reaction yet; I am sure it is coming. Ymblanter ( talk) 05:22, 9 August 2023 (UTC)
Guderian has a nice terse summary of latest updates; waiting for an RS to issue similar quotes. – SJ + 11:06, 9 August 2023 (UTC)
Schoop Lab 2023-08-09 said:
- 1. Samples following the described synthesis are multi-phase
- 2. Single crystals of an apatite phase can be isolated and are transparent. Our SXRD solution agrees with published powder pattern
- 3. Cu doping on Pb site seems not feasible based on formation energy calculations
- And finally: even if we assume the Cu doped structure to be correct, theory predicts (for the given structure) a magnetic ground state due to localized flat bands.
I.e. they haven't measured properties yet, but a very detailed material structure analysis of both synthesized samples and theoretical models of the structure would suggest that the resulting products following the synthesis steps do not have the crystal structure proposed, and that they are unlikely to be superconducting.
from the Beijing National Laboratory for Condensed Matter Physics at IoP-CAS:
- Lee et al. reported that the compound LK99, with a chemical formula of Pb_{10−x}Cu_x(PO_4)_6O (0.9<x<1.1), exhibits room-temperature superconductivity under ambient pressure. In this study, we investigated the transport and magnetic properties of pure Cu_2S and LK-99 containing Cu2S. We observed a sharp superconducting-like transition and a thermal hysteresis behavior in the resistivity and magnetic susceptibility. However, we did not observe zero-resistivity below the transition temperature. We argue that the so-called superconducting behavior in LK-99 is most likely due to a reduction in resistivity caused by the first order structural phase transition of Cu_2S at around 385 K, from the β phase at high temperature to the γ phase at low temperature.
I.e. the Cu2S impurity that had been mentioned in several places already seems like they might actually be responsible for QERC's "superconductor-like" resistivity and magnetic susceptibility graph, where a rapid drop in resistivity occurrs at temperatures similar to that reported in QERC's initial papers. Cu2S undergoes a first-order phsae transition at around 385K, where it's resistivity drops by several orders of magnitudes, and it's diamagnetism also exhibits a sharp transition, albeit not as pronounced as the resistivity drop.
The references list for this article is absurd now. Can the laymen leave the experts alone and not force them to reference every single bloody thing 94.14.250.118 ( talk) 04:05, 10 August 2023 (UTC)
"2514.2 AMU /(sin(60°)*9.843*9.843*7.428 Å^3)". WolframAlpha (calculation). Archived from the original on 29 July 2023. Retrieved 29 July 2023.— Preceding unsigned comment added by 94.14.250.118 ( talk) 04:08, 10 August 2023 (UTC)
The user LS-Phys-86 sent me the following email asking for help editing the article (I suspect they don't understand how Wikipedia works and the purpose of the Talk page):
Both links, [27] and [91], lead to a same paper. [27] is correct. Please recover the [b1] superscript from this paper's reference.
I don't really have time to look into this, but if anyone wants to take a look and possibly help this user with their edit request, they can. RaphaelQS ( talk) 19:20, 11 August 2023 (UTC)
![]() | This
edit request has been answered. Set the |answered= or |ans= parameter to no to reactivate your request. |
change " [1]" to " [2] [b 1]" LS-Phys-86 ( talk) 21:07, 11 August 2023 (UTC)
References
I count no fewer than 18, but I may have missed one or two. I also notice the top four editors of this article are well-tenured, and one an admin. AS a three-month-old, help me understand how cataloging potentially bogus research doesn't violate any number of rules related to reliable sourcing and WP not being a dumping-ground for arbitrary information. With about 70 other sources that appear more reliable, isn't there plenty enough to work with already? I'm especially concerned about this because I just declined to add another one from an undisclosed probable COI IP editor. How many of the 18 are included because of similar shenanigans? Xan747 ✈️ 🧑✈️ 14:36, 14 August 2023 (UTC)
Apparently the pure stuff is purple:
https://www.nature.com/articles/d41586-023-02585-7#ref-CR6
Or Purple-brown according to the arxiv paper:
https://arxiv.org/pdf/2308.06256.pdf
©Geni ( talk) 07:31, 17 August 2023 (UTC)
It's the speed of this rapidly updating article that shows the true value of Wikipedia and it's contribution to the fourth estate.
It also shows how science is getting better performing replication & checking of data. Something that it has egregiously bad at in the past, leading to years of misunderstandings & leading to both harm & & the destruction of life on ea thanks to everyone involved in this article. Thankyou for rapidly bringing me up to date 82.6.88.43 ( talk) 08:22, 22 August 2023 (UTC)
Now that superconductivty in copper-doped lead oxyapatite has more or less been debunked, should the article be reworked to provide a summary of research rather than a blow by blow account? For example, replace the table of theoretical papers with a few sentences, with citations, summarising the predictions.
On the other hand, it would seem sensible to add the cleaner synthesis route from the Max Planck Institute to the synthesis section. Lavateraguy ( talk) 11:35, 28 August 2023 (UTC)
Just putting this up for possible update to the article. I'm not sure where we're at wrt popular press versus new scientific papers and peer reviewed stuff. This piece mentions that the authors updated the patent to include silicon and copper doping, which are not in the article #Other discussion by authors as I press "save". ☆ Bri ( talk) 17:25, 29 August 2023 (UTC)
it's gonna work at room temperature and oven temperature so you can put your pc into your oven!
{{
jokes}}
Tweeeg (
talk) 20:19, 14 September 2023 (UTC)
Could be worth adding to the article: https://twitter.com/pronounced_kyle/status/1742588127628361809 Artem S. Tashkinov ( talk) 00:05, 5 January 2024 (UTC)
![]() | This article contains a partial translation of LK-99 from zh.wikipedia. ( 1196050999 et seq.) |
Te0sla ( talk) 10:59, 17 January 2024 (UTC)
The American Physical Society meeting notice (currently citation #3) lists sulfur as one of the chemical constituents. This is at odds with
#Chemical properties and structure. ☆
Bri (
talk) 22:45, 7 February 2024 (UTC)
Cite error: There are <ref group=b>
tags on this page, but the references will not show without a {{reflist|group=b}}
template (see the
help page).
![]() | This article is rated B-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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![]() | This article has been
mentioned by multiple media organizations:
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Two edits in
Special:Diff/1167517849/1167516509 removed use of the citation {{
r|padavic-c-20230726}}
(causing a syntax error) and introduced new wording at odds with
MOS:CLAIMED in the Wikipedia Manual of Style. These have been temporary reverted in
Special:Diff/1167521503. (Would encourage
Osunpokeh to attempt their edits again in a way that do not break the page or introduce problematic wording.) —
Sladen (
talk) 07:31, 28 July 2023 (UTC)
Reflecting on articles about various miracle-cure physics and science articles: we could use a style for tagging / talking about claimed advances that deviate dramatically from existing models, with limited intervening discoveries or confirmed theoretical underpinning. <longer style rant + comments moved to User:Sj/miracles> – SJ + 09:17, 1 August 2023 (UTC)
2607: above suggested we would know soon whether this has "panned out or not". This may be true if there are a series of positive results. But if there are only negative results, this is unlikely, as negative claims are hard to prove. Some of the developments that might be expected even if results are negative for weeks:
Inconclusive support
Inconclusive disconfirmation
– SJ + 20:53, 29 July 2023 (UTC)
Related comment by Sabine Hossenfelder - Wild guess: the first reproduction attempts will find the material isn't sc, there will be some discussion about whether the stuff was synthesized correctly, then we'll never hear about it again.
Right now we have three partial success entries in the replication table. All have shown video of a tiny and thin flake, which is perhaps 100x lighter than the object shown w/ partial levitation in the initial paper. Pablogelo has glossed them as 'Preliminary results unavailable' and not 'partial success' which seems right, since this is a minimal result, with no data shared beyond grainy video. (Also: all labs tried to produce much larger quantity than those flakes, so there is likely be a reason they're all showing such tiny pieces through a magnifying glass; we should assume that larger fragments don't show this property. Also, none have showed their flakes alongside flakes of known diamagnets like graphite for comparing strength of interaction.) – SJ + 17:08, 1 August 2023 (UTC)
Removed two lines from the article (no information on the researcher, lab, or any followup; minimal detail in videos). Please add any other questionable replication reports here; we can check on them to see if they have published anything more serious. See also this Wordpress and this forum thread for sporadically-updated lists. – SJ + 17:29, 1 August 2023 (UTC)
Any reported replication efforts with no results, or with teaser images/videos but no results, can go here. They can be moved back if/when they publish.
As the number of published experiments grows, the article should probably just summarize the most notable, but we can keep track of the longer list of verifiable experiments by notable people/labs here or on a subpage. – SJ + 09:21, 3 August 2023 (UTC)
Should [ these] guys be included too. Worcester Polytechnic Institute in Worcester MA in the US. Ittiz ( talk) 13:17, 4 August 2023 (UTC)
Group | Country | Status | Result | Notes |
---|---|---|---|---|
Shanghai University | ![]() |
Unpublished | Synthesized LK-99 powder, saw no diamagnetism. | News report: on-site interview by reporter
[1]
Not Included: unpublished, limited media coverage, very simple contribution. |
Qufu Normal University | ![]() |
Unpublished | LK-99 sample had non-zero resistance. | Press coverage:
[2]
Not Included: ? |
AGH University of Krakow | ![]() |
Unpublished | Images showing partial levitation of a small sample in response to magnetic field. No significant electrical conductivity observed. | Photographs shared on Twitter:
[3]
Team including Prof. Konrad Szaciłowski and Dr. Agnieszka Podborska at AGH University of Krakow. [4] Media Coverage: [5] Not Included: unpublished, limited media coverage, no major contribution. |
Lebedev Physics Institute | ![]() |
Unpublished | Structure confirmed with X-ray diffraction. No diamagnetism was observed. High resistance observed with 4-point probes method. Resistance increases when temperature decreases. | Statement by Lebedev Physics Institute:
[6]
Not Included: unpublished, limited-reliability media coverage. |
National Taiwan University | ![]() |
Unpublished | Diamagnetism observed. Non-zero resistance, no superconductivity. | Li-min, et al.
Press coverage: [11] Not Included: unpublished, limited media coverage, no major contribution. |
University of Wollongong | ![]() |
Unknown | — | Dr. Xiaolin Wang et al.
[12]
Not Included: No results / lacks media reporting. |
Faculty of Mathematics and Physics, Charles University (Prague) | ![]() |
Started on 2023-08-03 | A false mixture of copper and phosphorus in the ratio of 1:3 instead of 3:1 lead to an unsuccessful synthesis. A new attempt is ongoing. | Department of Condensed Matter Physics
[13]
Not included: Lacks media reporting. |
University of Science and Technology of China | ![]() |
Results unavailable | 8/1: Video showing diamagnetism of small sample. | Video uploaded to
Zhihu.
[14]
better source needed
Not included: Lacks media reporting. |
Iris Alexandra [a 1] & Moscow Engineering Physics Institute | ![]() |
Unpublished | Photograph of small sample levitating in glass tube. | Sample synthesis and photograph by pseudonym Iris Alexandra.
[15] Posting on
Twitter. Claimed by this account to have analysis by
Moscow Engineering Physics Institute.
[16]
Not included: No confirmation from media of link with institute. |
Wuhan University of Science and Technology | ![]() |
Unpublished | Very brief video of levitation of sample, allegedly showcasing flux pinning. |
[19]
[20]
Claimed to have been produced by Zhang Xiang at Wuhan University; not confirmed by Xiang or the university; no further context or details. Not included: Lacks media reporting. |
Queensland University of Technology | ![]() |
Unpublished | Not Reported |
[21]
Not included: No results / lacks media reporting. |
Theoretical studies | ||||
Institute of Mathematical Sciences, Chennai and IIT Madras | ![]() |
Preliminary | Theorises a mechanism for superconductivity involving copper chains in LK-99. | arXiv:
G. Baskaran
[22]
Not included: No results / lacks media reporting. |
KAIST and Johns Hopkins | ![]() ![]() |
Preliminary | DFT Analysis of a two-orbital Hubbard model, concluding it would not exhibit superconductivity, but not ruling out other Cu dopings. | arXiv: Oh & Zhang
[23]
Not included: No results / lacks media reporting. |
University of California, Irvine and University of Toronto | ![]() ![]() |
Preliminary | Proposed a minimal tight-binding model which reproduces the main features of the flat bands in LK-99. | arXiv: Omid Tavakol & Thomas Scaffidi
[24]
Not included: No results / lacks media reporting. |
Confusing graph in isolation. There's no clear dropoff, no clear T_c, and a lot of noise at low resistance. While superconducting measurements regularly go down to 1e-7 Ohms, here noise dominates at 1e-5 Ohms. They mention in the preprint the artefact around 230-250K could be sensor error. We should caption carefully.
References
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was invoked but never defined (see the
help page).{{
cite web}}
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help)}
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was invoked but never defined (see the
help page).{{
cite web}}
: Missing pipe in: |3=
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help); Text "access-date=2023-08-05" ignored (
help)
{{
cite web}}
: Missing pipe in: |3=
(
help); Text "access-date=2023-08-05" ignored (
help)
Let's use this section to discuss reliability of specific sources.
A tweet, facebook, bilibi, youtube isn't a reliable source and should be avoided when updating this article, multiple users are forgetting it when editing the section on replications, please refer to: /info/en/?search=Wikipedia:Reliable_sources I would suggest a mod to watch that section more thoroughly and a clean-up is needed — Preceding unsigned comment added by Pablogelo ( talk • contribs) 17:10, 1 August 2023 (UTC)
+1. In terms of usefulness as a primary source (a clear record of what a verifiable person did, as plausibly claimed by them + not just attributed to them), I would say
And our biggest challenge currently is we need more unambiguous papers. – SJ + 17:52, 2 August 2023 (UTC)
According to the claims of this post on YCombinator, LK-99 may not be a superconductor "in a traditional sense". To quote, "it should be first noted that this substance is not a strict superconductor in the current theory." It is said to be engineered with certain tradeoffs, removing properties typically associated with superconductors (e.g. Meissner effect) to enable operation at room temperature. Thus it would be less likely to be classified as a superconductor, even if it did conduct current with zero resistance. The post received "substantial updates" since its initial release, which fixed "possible misreadings and inaccuracies".
The speculation that specifically caught my attention was "This whole discourse should make you more careful to conclude whether LK-99 is a superconductor or not, because we may well end up with a revised definition of SC as a result." This may or may not be notable, but I thought the source was worth surfacing if not done so already.
https://news.ycombinator.com/item?id=36996337 — Preceding unsigned comment added by 68.10.151.165 ( talk) 03:56, 5 August 2023 (UTC)
different phrases have the same color while the same phrase also has a different color, I guess the color is based on outcome but wouldn't it be smarter then to color the "Result" Column? Littlerootlodge ( talk) 08:39, 2 August 2023 (UTC)
This seems fine. But: is the current color-setup automatically generated by the template? – SJ + 02:31, 3 August 2023 (UTC)
Partial success and partial failure are basically the same color and it's driving me crazy. Is there no respect for the color blind? There's gotta be a better way to color code this stuff. DontLikeRedesign ( talk) 12:16, 8 August 2023 (UTC)
These tables should be concise overviews to inform the article, not hat racks for any unreviewed preprints or claims that emerge. It so happens that some of the very early analyses were from highly notable labs. But in general these tables should be a selection of the most relevant work at any point in time. My take:
The tables should also be more concise: perhaps we can drop the References column; refs should be inline with claims, wherever possible, and the rest can be attached to a "Media mentions:" line at the end of publication status. – SJ + 11:56, 3 August 2023 (UTC)
The mechanism section needs work, and should be shorter. While some theories have been proposed, none is known; and in the absence of observed sc it's hard to describe a potential mechanism for a potential observation w/o implying the observation has occurred. – SJ + 08:33, 8 August 2023 (UTC)
I removed the following section, as it's synth from old papers. The article should only contain summaries of mechanisms that are clearly described by secondary sources, or in quotes from interviews, or proposed specifically for this material (e.g., a new paper on "mechanism for LK-99 levitation", like the ferromagnetic half-levitation paper). – SJ + 08:56, 8 August 2023 (UTC)
- Proposed mechanism for diamagnetism
Although the Meissner effect cannot be seen in one-dimensional superconductors, Hyun-Tak Kim claims that a sample of LK-99 shows a strong diamagnetism of 5450 times that of graphite, despite its low purity, although no Meissner effect was observed. A suggestion is that the measured three-dimensional LK-99 sample has a polycrystal structure which may result in appearance of both superconductive and diamagnetism. Chair also pointed out that single crystals and composites can have very different properties.
Currently, the section is misleading QCentre supports both SQW and and BR-BCS while it . In fact, SQW is Kwon's theory(sukbae-2023). Unfortunately, QCentre already stated they requested to discard the paper and they disagree to publish the paper. BR-BCS is Hyun-tak Kim's theory. Hyun-tak Kim wrote(ref: SBS interview) the paper(sukbae-2023-2) referring BR-BCS theory which QCentre team agreed. Their original theory is none of them. It was electron superfluid(sukbae-2023b). It is removed since https://en.wikipedia.org/?title=LK-99&diff=1169305425&oldid=1169304194. Since Hyun-tak Kim already finished LK-99 with BR-BCS in 2022(interview), both sukbae-2023b and sukbae-2023-2 are QCentre's official papers with different view with or without Hyuntak's theory. Since only Hyun-tak take interviews while Sukbae doesn't, confirming QCentre still keeps their original theory in sukbae-2023b will be hard at the moment. But confirming QCentre replaced sukbae-2023-2 with sukbae-2023b will be also impossible. At least the superfluid theory looks more important than SQW by citating QCentre.
The mechanism is complex and much more work is warranted as we can see from prior work in this area which was established through extensive theory connected with metrology. Adding relevant references from Rev.Mod.Phys to give the context is warranted. -- QuantumJIM1994 ( talk) 21:11, 8 August 2023 (UTC)
The prior brevity of this section which only cited a single arxiv paper from LBNL is too short. It risks making that single paper as the sole source (which can still be incorrect) The replication by other groups is relevant within the context of the LK99 research being new and fast changing. Also to note are the additional insights provided in the references. Citations to critical work listing the gaps should not be deleted to allow readers to have knowledge of the required future work. -- QuantumJIM1994 ( talk) 21:11, 8 August 2023 (UTC)
Youknowone ( talk) 12:44, 8 August 2023 (UTC)
This patent [2] related to LK-99 mentions another patent [3] filed by Salvatore Pais. Apart from these WP:PRIMARY sources there seems to be no WP:RS connecting Pais to this article.
As such I have to ask: Is it really helpful to simply place a link to Pais in the "See also" section ?
I think not. Lklundin ( talk) 18:02, 8 August 2023 (UTC)
On the page for that guy it links back here to LK-99 - this to me looks like link farming. 94.14.250.118 ( talk) 18:22, 8 August 2023 (UTC)
Now we finally got serious people working on the topic: [4]. They characterized the samples and do not see any superconductivity. Not including this to the article because there was no media reaction yet; I am sure it is coming. Ymblanter ( talk) 05:22, 9 August 2023 (UTC)
Guderian has a nice terse summary of latest updates; waiting for an RS to issue similar quotes. – SJ + 11:06, 9 August 2023 (UTC)
Schoop Lab 2023-08-09 said:
- 1. Samples following the described synthesis are multi-phase
- 2. Single crystals of an apatite phase can be isolated and are transparent. Our SXRD solution agrees with published powder pattern
- 3. Cu doping on Pb site seems not feasible based on formation energy calculations
- And finally: even if we assume the Cu doped structure to be correct, theory predicts (for the given structure) a magnetic ground state due to localized flat bands.
I.e. they haven't measured properties yet, but a very detailed material structure analysis of both synthesized samples and theoretical models of the structure would suggest that the resulting products following the synthesis steps do not have the crystal structure proposed, and that they are unlikely to be superconducting.
from the Beijing National Laboratory for Condensed Matter Physics at IoP-CAS:
- Lee et al. reported that the compound LK99, with a chemical formula of Pb_{10−x}Cu_x(PO_4)_6O (0.9<x<1.1), exhibits room-temperature superconductivity under ambient pressure. In this study, we investigated the transport and magnetic properties of pure Cu_2S and LK-99 containing Cu2S. We observed a sharp superconducting-like transition and a thermal hysteresis behavior in the resistivity and magnetic susceptibility. However, we did not observe zero-resistivity below the transition temperature. We argue that the so-called superconducting behavior in LK-99 is most likely due to a reduction in resistivity caused by the first order structural phase transition of Cu_2S at around 385 K, from the β phase at high temperature to the γ phase at low temperature.
I.e. the Cu2S impurity that had been mentioned in several places already seems like they might actually be responsible for QERC's "superconductor-like" resistivity and magnetic susceptibility graph, where a rapid drop in resistivity occurrs at temperatures similar to that reported in QERC's initial papers. Cu2S undergoes a first-order phsae transition at around 385K, where it's resistivity drops by several orders of magnitudes, and it's diamagnetism also exhibits a sharp transition, albeit not as pronounced as the resistivity drop.
The references list for this article is absurd now. Can the laymen leave the experts alone and not force them to reference every single bloody thing 94.14.250.118 ( talk) 04:05, 10 August 2023 (UTC)
"2514.2 AMU /(sin(60°)*9.843*9.843*7.428 Å^3)". WolframAlpha (calculation). Archived from the original on 29 July 2023. Retrieved 29 July 2023.— Preceding unsigned comment added by 94.14.250.118 ( talk) 04:08, 10 August 2023 (UTC)
The user LS-Phys-86 sent me the following email asking for help editing the article (I suspect they don't understand how Wikipedia works and the purpose of the Talk page):
Both links, [27] and [91], lead to a same paper. [27] is correct. Please recover the [b1] superscript from this paper's reference.
I don't really have time to look into this, but if anyone wants to take a look and possibly help this user with their edit request, they can. RaphaelQS ( talk) 19:20, 11 August 2023 (UTC)
![]() | This
edit request has been answered. Set the |answered= or |ans= parameter to no to reactivate your request. |
change " [1]" to " [2] [b 1]" LS-Phys-86 ( talk) 21:07, 11 August 2023 (UTC)
References
I count no fewer than 18, but I may have missed one or two. I also notice the top four editors of this article are well-tenured, and one an admin. AS a three-month-old, help me understand how cataloging potentially bogus research doesn't violate any number of rules related to reliable sourcing and WP not being a dumping-ground for arbitrary information. With about 70 other sources that appear more reliable, isn't there plenty enough to work with already? I'm especially concerned about this because I just declined to add another one from an undisclosed probable COI IP editor. How many of the 18 are included because of similar shenanigans? Xan747 ✈️ 🧑✈️ 14:36, 14 August 2023 (UTC)
Apparently the pure stuff is purple:
https://www.nature.com/articles/d41586-023-02585-7#ref-CR6
Or Purple-brown according to the arxiv paper:
https://arxiv.org/pdf/2308.06256.pdf
©Geni ( talk) 07:31, 17 August 2023 (UTC)
It's the speed of this rapidly updating article that shows the true value of Wikipedia and it's contribution to the fourth estate.
It also shows how science is getting better performing replication & checking of data. Something that it has egregiously bad at in the past, leading to years of misunderstandings & leading to both harm & & the destruction of life on ea thanks to everyone involved in this article. Thankyou for rapidly bringing me up to date 82.6.88.43 ( talk) 08:22, 22 August 2023 (UTC)
Now that superconductivty in copper-doped lead oxyapatite has more or less been debunked, should the article be reworked to provide a summary of research rather than a blow by blow account? For example, replace the table of theoretical papers with a few sentences, with citations, summarising the predictions.
On the other hand, it would seem sensible to add the cleaner synthesis route from the Max Planck Institute to the synthesis section. Lavateraguy ( talk) 11:35, 28 August 2023 (UTC)
Just putting this up for possible update to the article. I'm not sure where we're at wrt popular press versus new scientific papers and peer reviewed stuff. This piece mentions that the authors updated the patent to include silicon and copper doping, which are not in the article #Other discussion by authors as I press "save". ☆ Bri ( talk) 17:25, 29 August 2023 (UTC)
it's gonna work at room temperature and oven temperature so you can put your pc into your oven!
{{
jokes}}
Tweeeg (
talk) 20:19, 14 September 2023 (UTC)
Could be worth adding to the article: https://twitter.com/pronounced_kyle/status/1742588127628361809 Artem S. Tashkinov ( talk) 00:05, 5 January 2024 (UTC)
![]() | This article contains a partial translation of LK-99 from zh.wikipedia. ( 1196050999 et seq.) |
Te0sla ( talk) 10:59, 17 January 2024 (UTC)
The American Physical Society meeting notice (currently citation #3) lists sulfur as one of the chemical constituents. This is at odds with
#Chemical properties and structure. ☆
Bri (
talk) 22:45, 7 February 2024 (UTC)
Cite error: There are <ref group=b>
tags on this page, but the references will not show without a {{reflist|group=b}}
template (see the
help page).