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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