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.
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.
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.
Do you have a link to more than one showing complete levitation?
One of those has already been admitted to being outright faked:
https://www.tomshardware.com/news/lk-99-video-fraud-taken-do...
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.
1. https://twitter.com/andrewmccalip/status/1687405505604734978
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
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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.
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?
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.
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.
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.
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.
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-...
If the sample they claim is superconducting isn't superconducting; why should we assume that this material is a superconductor at all? Because of some vague idea that their prof thought it might be more than 2 decades ago?
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?
my favorite xkcd: https://xkcd.com/683/
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.
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.
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.
The Korean team needs to disclose any alternative formulations or just accept failure and move on.
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.
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...
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.
We're separately 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?
Combining both available evidence and author credibility is completely valid and leads one to the conclusion that this is incorrect until proven otherwise. It's not like we're solely dismissing the claim because the authors have poor credibility.
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.
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.
If it can't be verified, it remains an unverified claim, not necessarily a falsehood.
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.
They apparently weren't actively researching that material between 1999 and 2018.
“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 and don’t have anything solid after seriously working on it for 4 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.
No scientist can do real work if they are constantly distracted by random internet folk like this.
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.
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.
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?
The preprint you are citing is explicitly dismisses the sharp transition seen as being non-superconducting.
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.
The original samples are now under testing at a national lab in SK.
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.
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.
It still hugely weakens the levitation effect as evidence for SC, but "conclusively show that it is not superconductivity" is not quite true.
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.
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.
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.
As far as I am concerned, all of the previous results are entirely consistent with the peking paper, not positive.
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.