4 ms·
> 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 the
by brucethemoose2 3y ago
> 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.
- whatshisface 3y agoLevitation with a corner touching the magnet can be accomplished by iron. It's what iron filings do when you put them on a magnet!
- brucethemoose2 3y agoThere 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.
- marcosdumay 3y agoI haven't seen any such video with a high credibility stance after it, like the author using the real name.
- carabiner 3y agoAre any of those from legit research institutions? I know there have been a bunch of fake hover videos in the past 48 hours.
- drdeca 3y agoI 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?
- hackerlight 3y agoI recall one showing full levitation (BilliBilli anon poster). If there is a different video, the poster above should link it.
- fnordpiglet 3y agoThe iris videos were full levitation
- rrssh 3y agoWe distinguish between videos and photos in this context.
- Jweb_Guru 3y agoIris 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.
- fnordpiglet 3y agoTrue. 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!
- lamontcg 3y ago> 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-down https://www.tomshardware.com/news/lk-99-video-fraud-taken-do...
- brucethemoose2 3y agoI 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.
- crdrost 3y agoI believe you are remembering [1] and it is not a full levitation. 1. https://twitter.com/andrewmccalip/status/1687405505604734978 https://twitter.com/andrewmccalip/status/1687405505604734978
- zhangjunphy 3y agoSome 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 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.
- 3y ago
- jacquesm 3y agoI 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.
- Waterluvian 3y agoAll 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.
- fooker 3y ago> 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.
- penjelly 3y agothank you for providing nuance
- cptaj 3y agoThis 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.
- lumost 3y agoUnfortunately 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-fusion/ https://www1.grc.nasa.gov/space/science/lattice-confinement-...
- deleted 3y ago[deleted]
- archgoon 3y ago> Even this sample could be marginal, going by the original paper. 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?
- Jweb_Guru 3y agoThat'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?
- gehwartzen 3y agoPeople always underestimate how much time physical science takes and how small normal steps are. my favorite xkcd: https://xkcd.com/683/ https://xkcd.com/683/
- kijin 3y agoCalling 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.
- Osmium 3y agoScientists 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.
- kijin 3y agoThere 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.
- ThePhysicist 3y agoIt 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.
- SanderNL 3y ago[flagged]
- highwaylights 3y agoSpeaking as a layperson and casual observer, I understood some of the words in this thread.
- klabb3 3y agoI 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.
- computerfriend 3y agoI don't think an LLM is capable of this kind of sarcasm (yet).
- kergonath 3y agoI 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).
- SanderNL 3y agoI transgressed and take full responsibility. Couldn’t resist.