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Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by ayakang31415 on Tuesday August 08, 2023 @06:47PM (#37056512)
As I feared, it is no use at all at this stage to claim anything about LK-99 as every synthesized LK-99 seems different each time. We have to have a thorough analysis on the sample directly provided by Lee and Kim.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by brucethemoose2 on Tuesday August 08, 2023 @07:11PM (#37056703)
> We have to have a thorough analysis on the sample directly provided by Lee and Kim.

Even this sample could be marginal, going by the original paper.

But there has been plenty of "locked" levitation and lots of zero conductance failures. I believe LK-99 a finicky topological superconductor thats going to give researchers headaches for years, not something that will suddenly be a bulk superconductor with just the right synthesis in the coming months.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by cptaj on Tuesday August 08, 2023 @07:32PM (#37056874)
This is my intuition as well.

Hopefully the controversy doesn't cloud researcher's judgement and cause us to miss out on the technology just because it was way more nuanced than first appeared.

It might also be that everyone loses interest and the original team get the extra time they needed to work in peace and make a comeback.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by lumost on Tuesday August 08, 2023 @08:16PM (#37057205)
Unfortunately such bold claims can strongly effect researchers ability to work on this in the future.

The original cold fusion release has had an overhang on any studies of low energy nuclear reactions. Regardless of whether they have any bearing on energy production.

As an example of this, it is obvious and known that metallic lattices can lower the energy barrier of a nuclear reaction. However the underlying physics of how much screening and when is illusive - and their is a high correlation of quackery with any attempts at studying these systems.

https://www1.grc.nasa.gov/space/science/lattice-confinement-...

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whatshisface on Tuesday August 08, 2023 @07:28PM (#37056839)
Levitation with a corner touching the magnet can be accomplished by iron. It's what iron filings do when you put them on a magnet!
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by brucethemoose2 on Tuesday August 08, 2023 @07:54PM (#37057053)
There have been multiple videos of tiny LK99 specs completely levitating on single magnets, and resisting motion when pushed, and staying afloat when the magnet is inverted.

That is not possible in any known material. Unless thats an array of very elaborate fakes, its a RT superconductor.

But the simulation papers and conductance tests make me suspect its a topological superconductor that would fail such tests.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by lamontcg on Tuesday August 08, 2023 @08:32PM (#37057315)
> There have been multiple videos of tiny LK99 specs completely levitating on single magnets, and resisting motion when pushed, and staying afloat when the magnet is inverted.

One of those has already been admitted to being outright faked:

https://www.tomshardware.com/news/lk-99-video-fraud-taken-do...

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by brucethemoose2 on Tuesday August 08, 2023 @08:36PM (#37057339)
I havent seen this video.

I am on mobile now, I will have to go back through my history and check the claims... But one such reproduction is from the Meissner or Bust channel. They have been documenting the production for days, and IIRC they showed full levitation on a single magnet.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by crdrost on Tuesday August 08, 2023 @09:07PM (#37057564)
I believe you are remembering [1] and it is not a full levitation.

1. https://twitter.com/andrewmccalip/status/1687405505604734978

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by zhangjunphy on Tuesday August 08, 2023 @10:19PM (#37057997)
Some additional context here. The author has a further statement, in which he apologizes that the previous video was misleading due to two points: 1. The sample was not LK99. 2. Both the larger piece held by the tweezers and the smaller levitating one were from the same sample. But he also states that no tricks of any kind were used nor the video was edited.

So, some other material levitating itself in seemingly room temperature?

Currently this guy is practically using his real name, with his university and professor exposed. It takes some courage to lie at this point.

link(in Chinese): https://bilibili.com/video/BV1Zh4y1r7XL

======================

Edit: People sometimes speak in convoluted ways. I feel "The sample was not LK99" could have two interpretations here: 1. It is a completely different compound. 2. It is a derivative from LK99 with a different synthesis/doping method.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by imtringued on Wednesday August 09, 2023 @09:47AM (#37062570)
>Currently this guy is practically using his real name, with his university and professor exposed. It takes some courage to lie at this point.

No, it doesn't. It is a nine second video. Not a research paper. Right now the topic is being hyped up and you might care but next year nobody is going to give a damn about some random video uploaded to bilibili.

Why does everyone on HN pretend that even the smallest of missteps is going to end a reserachers career and therefore even videos with almost no effort put into them, that to feed the rumor mills, are somehow the paragon of truth?

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by vinnyvichy on Wednesday August 09, 2023 @10:43AM (#37063458)
There's a third interpretation: he took an x-ray of both bits of the sample and found that the XRD pattern of the levitating flake didn't match LK99's
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by ummonk on Wednesday August 09, 2023 @01:59AM (#37059184)
That video was so obviously not LK-99 I doubt anyone sane was fooled by it (anybody who has played with magnets knows that’s how ferrous metal hangs off of them).

We’ve seen proper levitation of specks that hasn’t been falsified yet.

That said, I believe theory has shown it’s actually possible for a diamagnetic object to fully levitate over a magnet as long as it’s light enough, but unlike a flux-pinned superconductor, it will only levitate over the center of the magnet, as is happening in all the levitation videos.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by jacquesm on Tuesday August 08, 2023 @08:34PM (#37057322)
I have yet to see a video that I would say is 100% unambiguous and from a credible source. Lots of 'maybe's' and a couple where my fraud meter pegged and seems to have broken something inside.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Waterluvian on Tuesday August 08, 2023 @09:18PM (#37057633)
All it would take for me to begin playing much closer attention are a few credible labs saying, “we spent some time on this and we can reproduce it a little bit, sometimes. There’s something up but we’re not ready to throw the weight of our reputation behind it just yet.”

You’d think that with the current excitement and relative simplicity of the apparatus, labs all over would be putting in some weekend hours to muck about.

Consistency might be a problem for fabrication and commercialization.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fooker on Wednesday August 09, 2023 @05:14AM (#37060308)
> labs all over would be putting in some weekend hours to muck about.

That's unfortunately not how science is incentivized.

The lab reproducing this would get exactly zero academic credit. Maybe a day of press fame, but that's it.

On the other hand, once/if this is proven to be real, there would be thousands of labs racing to improve it and cite each other's work.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by drdeca on Tuesday August 08, 2023 @08:20PM (#37057229)
I thought there was just one video of it completely levitating, and that that one was somewhat questionable (having an unclear source, and being deleted by original poster)?

Do you have a link to more than one showing complete levitation?

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by hackerlight on Tuesday August 08, 2023 @09:41PM (#37057769)
I recall one showing full levitation (BilliBilli anon poster). If there is a different video, the poster above should link it.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fnordpiglet on Tuesday August 08, 2023 @09:48PM (#37057812)
The iris videos were full levitation
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by rrssh on Tuesday August 08, 2023 @11:51PM (#37058510)
We distinguish between videos and photos in this context.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Jweb_Guru on Wednesday August 09, 2023 @04:25PM (#37067896)
Iris photo is completely unconfirmed outside of "Twitter likes her." She said she would make a video over a week ago and never did. Additionally, due to the fleck being confined to a tube, it would not fall afoul of any proofs about ordinary ferromagnetic levitation being impossible.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fnordpiglet on Thursday August 10, 2023 @01:09AM (#37072203)
True. However no internet hottake will be a proof of anything. The fun is over and now it’s time for science to work it’s laborious work. Nothing has been proven, nothing confirmed. But it was fun!
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by carabiner on Tuesday August 08, 2023 @08:21PM (#37057236)
Are any of those from legit research institutions? I know there have been a bunch of fake hover videos in the past 48 hours.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by marcosdumay on Tuesday August 08, 2023 @10:54PM (#37058186)
I haven't seen any such video with a high credibility stance after it, like the author using the real name.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by penjelly on Tuesday August 08, 2023 @09:37PM (#37057754)
thank you for providing nuance
[dead]
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Jweb_Guru on Wednesday August 09, 2023 @04:26PM (#37067917)
That's exactly where I'm coming from here. The original evidence that had people cautiously optimistic has been thoroughly dismantled. It's not showing any unusual or inexplicable signs of superconductivity: no anomalously high diamagnetism, no anomalously low resistivity or IV curves, no heat capacity differences, it lacks a theoretical model, and all anomalous measurements can be completely explained in terms of known or predicted properties of its constituent materials. I don't even need to bring up the lack of credibility of most of the members of the lab, HT Kim's crackpot tendencies, or the fact that Qcentre misrepresented its affiliations for it to be clear that there's nothing to the original paper.

Yet people are arguing "it might still be a superconductor! Just an exotic type that no one can replicate and also doesn't look like a superconductor in any measurements!" Okay, so could any number of other compounds, many of which are far more promising than this one (e.g. some USOs have shown actual definite diamagnetism). Why should we care about this one?

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by gehwartzen on Tuesday August 08, 2023 @10:14PM (#37057971)
People always underestimate how much time physical science takes and how small normal steps are.

my favorite xkcd: https://xkcd.com/683/

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by kijin on Tuesday August 08, 2023 @11:02PM (#37058242)
Calling it "LK-99" seems to have been a mistake. It gives the impression that the term refers to a well-defined material, perhaps even a mass-produced product like "iPhone 14" or "RTX 4080". This explains all the calls for the original authors to send samples, as if you were ordering from AliExpress.

In reality, what we have is a family of lead-copper-phosphorus-oxygen compounds, each with a different crystal structure, some of which might or might not exhibit interesting properties.

If this hype doesn't fizzle out soon, scientists will probably converge on more neutral, precise terminology to refer to the various configurations in order to avoid talking past one another. Something like β-LK99-Cu-5-7.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Osmium on Tuesday August 08, 2023 @11:35PM (#37058423)
Scientists already have well-defined terminology for many of the crystal structures described, the LK-99 is just a shorthand for this synthesis product (and a convenient one at that, for anyone trying to keep up with the latest). I wouldn’t be too concerned!

Part of the reason we’re not using a full formula yet is that we don’t precisely know what it is (or, indeed, if it’s just one thing at all; the linked paper makes a good argument that this will necessarily be a mix of multiple phases if synthesized as-described). Once we know what it is, we can use one of several existing names.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by kijin on Wednesday August 09, 2023 @08:09AM (#37061437)
There should be a middle ground somewhere between an unwieldy chemical formula and a catchy product-like name.

For example 3,4-MDMA is a useful shorthand for people who want to be precise as to which isomer they're talking about, but don't want to spell out 3,4-methylene-dioxy-methamphetamine every time.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by ThePhysicist on Wednesday August 09, 2023 @03:05AM (#37059536)
It seems people are throwing around more and more random physics keywords without any type of evidence. What makes LK-99 a topological superconductor? Topological quantum states and the associated Majorana fermions have only been observed in their bound state so far (and only in highly engineered quantum systems), and there's absolutely no indication that they should exist in that material, at least I don't see how you could postulate that by observing levitation or measuring an IV curve in a bulk sample.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by SanderNL on Wednesday August 09, 2023 @03:12AM (#37059571)
The underlying quasiparticle braiding mechanism, together with the ceramic's unique hyper-fluxional alignment, is theorized to resonate with virtual gravitons.

This phenomenon enables stabilized superconductive lattices at room temperature.

What's more, the introduction of dual-harmonic topological oscillations—a novel concept—leads to a "negative friction" state where energy loss becomes almost non-existent. Coupled with the integration of monopolar time crystals, the discovery of LK99 transcends conventional physics, paving the way for revolutionary applications such as zero-loss power grids and time-locked computational matrices.

Its unique synergy of phase change, half-dimensionality, and room-temperature superconductivity makes it one of the most exciting breakthroughs in modern science.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by highwaylights on Wednesday August 09, 2023 @03:43AM (#37059737)
Speaking as a layperson and casual observer, I understood some of the words in this thread.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by klabb3 on Wednesday August 09, 2023 @03:48AM (#37059767)
I think you may have been duped by an LLM. I’m glad someone is finding a real use case for it, I just wish it were somewhere else.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by computerfriend on Wednesday August 09, 2023 @04:04AM (#37059869)
I don't think an LLM is capable of this kind of sarcasm (yet).
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by kergonath on Wednesday August 09, 2023 @04:10AM (#37059906)
I thought there were rules against using ChatGPT in comments here.

(For the uninitiated, this is a bunch of gibberish with a few science-y keywords for truthiness).

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by SanderNL on Wednesday August 09, 2023 @06:51AM (#37060874)
I transgressed and take full responsibility. Couldn’t resist.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by zargon on Wednesday August 09, 2023 @01:30PM (#37065971)
It was clearly a joke, not intended to fool anyone. People have been writing technobabble for at least a century before ChatGPT. https://en.m.wikipedia.org/wiki/Turbo_encabulator
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by delabay on Tuesday August 08, 2023 @07:38PM (#37056926)
The quality and depth of the analysis here far exceeds the work done by the original Korean team. It is very unlikely the Korean team has successfully manufactured the Cu-doped phase given the thermodynamic mountain required to climb, and its clear anybody attempting to replicate their recipe was essentially producing a random assortment of garbage.

The Korean team needs to disclose any alternative formulations or just accept failure and move on.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by ayakang31415 on Tuesday August 08, 2023 @07:53PM (#37057042)
The original Korean team paper was supposedly a rushed job because of inside fight at the research center, so it is expected the quality is poor by default. We still have to wait for a more polished proper research paper from the team to judge whether it is legit or not (APL material is their choice of journal I believe). We can speculate whether the Korean team has achieved superconductivity or they are under delusion based on replication papers published on arxiv, but such papers have never come under the scrutiny of peer review process as well. So I would reserve my conclusion about this at this stage. It is just frivolous to say whether LK-99 is superconductor or not for now.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by haldujai on Tuesday August 08, 2023 @10:52PM (#37058178)
> but such papers have never come under the scrutiny of peer review process as well.

Except that such pre-prints far outnumber the supportive pre-prints, are from verifiable scientists at reputable institutions, are in agreement with each other, and are not making claims of a shocking scientific breakthrough.

As there is no substantial evidence to support superconductivity claims it's reasonable to dismiss them until said group decides to provide evidence. If you recall the burden of proof is on the one making the claim.

> It is just frivolous to say whether LK-99 is superconductor or not for now.

I don't think it's frivolous given the distraction and resource-sink this has been.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by thkim on Tuesday August 08, 2023 @08:32PM (#37057314)
Original authors have been working on it for 23 years since they first found the material in 1999. They are part of private institution and have no incentive to rush the disclosure so that other labs can catch on their life's work. Authors already have stated they will publish more information next year. It's pretty arrogant to draw premature conclusions on quick analysis and demand the authors to disclose more information right now, when they are clearly not obligated to anything.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by bhouston on Tuesday August 08, 2023 @09:02PM (#37057519)
I’ve seen inside of privately funded research that doesn’t have publication requirements and sometimes it is driven by a combination of belief, passion and incompetence which leads to an avoidance of accepting failure. Not saying this is the case with this but please do not elevate private research above public research. There is actually less controls over the quality of private research.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by thkim on Tuesday August 08, 2023 @09:09PM (#37057572)
I did not say I consider private research in some sort of higher level than public research. I only said they have no incentive to do full disclosure right now. Without knowing exactly what they know, it is insulting to authors to describe, or even hint, them as avoiding to accept failture. It is simply unwarranted ad-hominem and not contributing anything to academic discussion at this point.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by haldujai on Tuesday August 08, 2023 @10:01PM (#37057899)
> It is simply unwarranted ad-hominem

When the authors/executives of a private research company are making fraudulent affiliation claims to established corporations and research universities it's actually very warranted to be dismissive of their claims in the absence of supportive evidence. Especially when there is growing evidence suggestive of failure.

This is not the behavior of ethical scientists and suggests malice.

Faking affiliation and refusing to provide supportive evidence both smell like a fundraising scam (i.e. running out of money and need to raise more to continue research seems like the simplest explanation for this behavior).

https://web.archive.org/web/20230806081911/https://koreajoon...

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by thkim on Wednesday August 09, 2023 @12:24AM (#37058670)
Since when is ad hominem a part of evaluating claims?
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by haldujai on Wednesday August 09, 2023 @12:49AM (#37058818)
Without getting into a philosophical discussion of whether ad hominem is ever appropriate.

This is, in fact, the opposite of ad hominem.

Ad hominem would suggest we are attacking the claim based solely on the author's credibility. In fact, multiple independent replication experiments failed and theoretical models suggest it doesn't work.

So instead of attacking the authors the question is should we be trusting them at their word, and the answer which is reasonably based on credibility seems to be no.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by thkim on Wednesday August 09, 2023 @01:09AM (#37058925)
Whether or not authors are credible, instead of the claims, is not a scientific discussion.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by haldujai on Wednesday August 09, 2023 @01:39AM (#37059064)
The science behind the claims is being scientifically discussed and the preponderance of available evidence provide no experimental or theoretical support.

We're also discussing the author's credibility as the claims cannot be verified by anyone but the authors. One example of a time we do this is the "disclosures" section of any academic publication.

Are you arguing someone with a conflict of interest and history of making fraudulent arguments should not be placed under heightened scrutiny?

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by pcrh on Wednesday August 09, 2023 @03:10AM (#37059564)
Preponderance of available evidence is irrelevant to assessing scientific claims of fact.

The original claims only need to be rigorously verified once. As it currently stands the original claims are claimed to have been partially replicated. What's needed now is the rigor.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by bhouston on Wednesday August 09, 2023 @09:36AM (#37062445)
> Preponderance of available evidence is irrelevant to assessing scientific claims of fact.

The issue is that trying to prove a negative is very hard in this case.

It is similar to me saying that there is a type of cat that floats, although most don't. It is very hard to prove me wrong because even if you find 1M cats that do not float, it doesn't mean that there is a type of cat you missed to find.

All we can say is that we tried to find cats in a thorough way and none of them float.

When that happens, it is often standard to turn the argument over to the one that is claiming that cats float -- prove that you have a cat that floats, rather than relying on me to prove that no cats float.

This is why people are saying we need to do an analysis of the SC sample from LK. If it is super hard to produce, but we can confirm that they made one, then it is true. Otherwise, it is probably best to assume that the claim isn't true.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by pcrh on Wednesday August 09, 2023 @02:54PM (#37066971)
Nobody is trying to prove a negative here. The initial claim is of a RT superconductor. The claim only needs to be rigorously verified once.

If it can't be verified, it remains an unverified claim, not necessarily a falsehood.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by haldujai on Wednesday August 09, 2023 @09:09PM (#37070571)
No one in this thread is saying the Korean researchers have a superconductor in their possession has been proven false.

We have an unverified claim of a significant discovery released in a pre-print that was taken on good-faith and replication experiments were attempted.

This has resulted in what can be described as a very thorough and publicized review process by multiple researchers qualified to serve as reviewers. As this was all done in good faith it is effectively analogous to the scientific standard of blinded peer review as no one was considering the author's credibility.

The conclusion of multiple reviews has been the equivalent of "recommend rejection, invitation to resubmit with major revisions". Major revisions being verification of superconductivity in the sample they possess and further details regarding synthesis and yield as what has been described is clearly not working as claimed.

The relevance of author credibility is for a confidence estimation that a superconductor has been discovered at this time. Obviously, if this was Argonne or [peer] one would be more confident than in a private research corporation with a history of claiming false affiliations to notable research institutions. This is not an ad hominem attack, it's a credibility assessment.

The current state is we have a flawed and effectively rejected manuscript making a significant claim. Looking at the authors credibility is an attempt to remain optimistic but this also points to low confidence.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fouc on Wednesday August 09, 2023 @01:05AM (#37058906)
The privately funded work didn't start until 2018 or 2019 I think?

They apparently weren't actively researching that material between 1999 and 2018.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by kergonath on Wednesday August 09, 2023 @04:16AM (#37059953)
> It's pretty arrogant to draw premature conclusions on quick analysis and demand the authors to disclose more information right now, when they are clearly not obligated to anything.

“Put up or shut up” is a very valid stance in the face of extraordinary claims backed by dodgy evidence. They are not obligated to anything, but then we don’t have to take them seriously. The mere fact that they’ve sat on it for 20 years is strange. So far, the community has responded as it should, with a proper mixture of excitement and skepticism, which results in renewed interest in lead apatites (which is fine, apatites are great). But when questions keep piling up, “we have the proof but we’re not going to share” is bound to cause some frustration.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by j16sdiz on Wednesday August 09, 2023 @04:46AM (#37060133)
Since when live AMA session and twitch demo an requirement for science?

No scientist can do real work if they are constantly distracted by random internet folk like this.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by kergonath on Wednesday August 09, 2023 @05:27AM (#37060378)
Nobody mentioned any of this. There are several tools commonly used for communications within the scientific community, including peer-reviewed articles, letters, preprints, and conferences. It’s hardly controversial.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by cthalupa on Wednesday August 09, 2023 @06:01AM (#37060564)
Well, it's important to keep this all in context: They did not want to release the paper, even as a preprint, at this point. The infighting in the group necessitated it when someone went off script and threw up the original shoddy paper, forcing them to release their marginally better one.

They had sent out some samples prior to this whole debacle, including to KENTECH (a Korean university focusing on energy technology), but are waiting to send out more samples specifically because they want to get a peer-reviewed article out there before they start sending them out to a broader audience.

I'm not saying LK-99 is a RTAPS, and current evidence seems to indicate it is almost certainly not one, but the broader LK-99 team seems to have been attempting to follow the normal process the whole time.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Levitating on Wednesday August 09, 2023 @06:02AM (#37060570)
From my understanding they haven't been actively researching during that time.

It should also be noted that the team most likely did not intend to disclose any information already.

"Currently, two papers concerning LK-99 are available on the preprint service arXiv, which does not conduct peer review, and a related past study was published in the Journal of the Korean Crystal Growth and Crystal Technology in April 2023. Kim has only co-authored one of the arXiv papers, while the other is authored by his colleagues at QERC, some of whom also applied for a patent on LK-99 in August 2022. Both papers present similar measurements, however Kim says that the second paper contains “many defects” and was uploaded to arXiv without his permission. In that paper, the work is described as opening a “new era for humankind”." - From the New Scientist

The "second paper" referenced here is actually the first that was published, in which Young-Wan Kwon is the third author. If Hyun-Tak Kim states that this paper was not published with his permisison it seems like Young-Wan Kwon prematurely published it on arxiv to be the third author. The other paper was submitted by Hyun-Tak Kim just two hours later, listing himself as the third author.

Furthermore, Young-Wan Kwon isn't related to the Q-Centre anymore as he resigned from the function of CTO.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by Accujack on Tuesday August 08, 2023 @07:06PM (#37056642)
Or everyone has to wait for the full paper to be released which supposedly includes some manufacturing steps not included in the leaked paper so that replication can happen properly.

The original samples are now under testing at a national lab in SK.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by bhouston on Tuesday August 08, 2023 @08:12PM (#37057170)
I disagree. I think that given the multiple failed attempts from numerous top tier labs we should say this isn’t a SC unless L&K share their sample and it proves to be.

Replication has failed pretty thoroughly.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by threeseed on Tuesday August 08, 2023 @11:09PM (#37058281)
> Replication has failed pretty thoroughly

As everyone seems to keep forgetting the original scientists said that less than 10% of their replication attempts was successful.

We don't have 10 replications total let alone 10 based on their exact process which is unknown to everyone except them at this point.

So not sure on what basis you can claim replication has thoroughly failed.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Tuesday August 08, 2023 @11:27PM (#37058376)
They have been able to replicate the levitation and then shown that it is not due to SC but ordinary ferromagnetism
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by threeseed on Wednesday August 09, 2023 @01:35AM (#37059049)
Which is a useful data point.

But the wide variety of samples indicates that there isn't convergence yet on what the intended process is. Until that happens any conclusions are just data points - nothing more, nothing less.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Wednesday August 09, 2023 @04:31AM (#37060032)
The fact that they were able to replicate the original effect (what people thought was flux pinning) that made everyone think it is superconductivity and then conclusively show that it is not superconductivity is pretty strong evidence.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by versteegen on Wednesday August 09, 2023 @09:34AM (#37062431)
That's exactly what I thought at first. And then I realised that the 'ferromagnetism+diamagnetism' article does not actually provide a mundane explanation of the "half levitation": They estimated that their sample had very strong diamagnetism -- at least the 2nd strongest of any known (non-SC) substance, assuming their sample was pure (but we can be certain it isn't, considering that they just had one tiny flake levitate), so quite likely the strongest. And superconductivity is a possible cause of diamagnetism.

I still think the chance it's a SC is really low, but "conclusively show that it is not superconductivity" is not quite true.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Wednesday August 09, 2023 @10:09AM (#37062905)
There is no meissner effect, so it is not superconductive. I worked in this field, the paper as described is pretty damning. I think your reasoning is motivated.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by photonerd on Wednesday August 09, 2023 @02:09AM (#37059244)
Stating with confidence that anything has been conclusively shown about it is a sign you’re arguing from a position not based on evidence.

There simply is not enough evidence to say anything yet. Claiming there is means you either don’t understand it or are willfully misrepresenting it. Either way: no.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Wednesday August 09, 2023 @04:36AM (#37060066)
The evidence that has come out so far against LK99 in the past few days is pretty strong (particularly the paper out of Peking), not conclusive but it would take some very strong results in the other direction to suggest we are seeing anything like superconductivity.

I have worked in the field of characterizing high temperature superconductivity, there appears to be a lot of motivated reasoning going on around this topic. I would love for this to pan out and while I was initially skeptical I thought there could be a chance. I think the evidence of the past two days has been pretty strong for the negative case and I have adjusted my likelihoods significantly downwards in response.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by photonerd on Wednesday August 09, 2023 @01:10PM (#37065698)
I agree that recent results have been negative. The reason why they were negative when other previous ones were more positive is, however, undetermined.

With a process that seems to be highly variable, and that the original paper had a only 1 in 10 chance of any success PLUS one that seems to be highly change to produce similar results (but unconfirmed if the same) I’m not too surprised at the high variability of the tests so far.

Frankly, I think it’ll be several years before we get anything close to more conclusive results in either direction. The replication results so far have been… enthusiastic but not exactly stringently controlled.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Wednesday August 09, 2023 @07:18PM (#37069706)
What positive results have their been that are unexplained by the Peking paper?

As far as I am concerned, all of the previous results are entirely consistent with the peking paper, not positive.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by dragonwriter on Wednesday August 09, 2023 @04:37AM (#37060069)
The original authors can’t consistently reproduce their results and the original authors haven’t made public sufficient information that others attempts at replication can even be judged as to whether they are doing the same thing the authors claim to have been doing are both negative indicators here on the claimed results more than on anything else.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fouc on Tuesday August 08, 2023 @11:24PM (#37058362)
* multiple successful attempts of levitation/flux pinning.

The hard part is going to be figuring out how to actually isolate the superconducting effect such that it can be tested. We already know the SC effect isn't uniformly spread throughout the ceramic.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by whimsicalism on Tuesday August 08, 2023 @11:26PM (#37058371)
Wow you are in denial
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by fouc on Tuesday August 08, 2023 @08:15PM (#37057193)
eh, most of the synthesized LK-99 out there by the different teams share enough commonalities and seem very promising from the levitation/flux pinning effects.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by gehwartzen on Tuesday August 08, 2023 @10:09PM (#37057945)
Honestly I'm excited by that. Seems like a big space opened up for exploration. I think over the next few years there will be several types of this composition with varying electro-magnetic properties.
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by hcks on Wednesday August 09, 2023 @05:34AM (#37060414)
> let’s invest even more time and resources on what doesn’t look at all like a dud
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by belter on Wednesday August 09, 2023 @07:10AM (#37060987)
Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by MissingAFew on Wednesday August 09, 2023 @08:04AM (#37061391)
Or Beijing, since they apparently have fully replicated it.

https://arxiv.org/abs/2308.04353

I don't know why so many institutions and scientists are so quick to call it nothing. It feels like hubris to me, the scientists in Korea spent many years on it, if it were so easy to dismiss I don't think that would have continued their research... right?

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by radioactivist on Wednesday August 09, 2023 @08:28AM (#37061639)
> The superconducting-like behavior in LK-99 most likely originates from a magnitude reduction in resistivity caused by the first-order structural phase transition of Cu2S

The preprint you are citing is explicitly dismisses the sharp transition seen as being non-superconducting.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by MissingAFew on Wednesday August 09, 2023 @09:18AM (#37062231)
Nah, I know. But it still looks like a similar material, no?

Even if it looks unlikely to be superconducting, I still think people should remain level headed about it. They spent a lot of time and effort on it.

Re:LK-99: Phonon Bands, Localized Flat Band Magnetism, Model... by EvgeniyZh on Wednesday August 09, 2023 @09:03AM (#37062034)
Well Occam's razor is to rescue. As for now "LK-99 is not superconductor" is the simplest claim consistent with all experimental evidence. That's not awfully specific, but since specifics are not very impactful, people won't rush to clarify it. If anyone (probably original authors) provide something that contradicts this claim then we'll need to revise it