40 ms·

Semiconducting Transport in LK99 reproduction attempt

613 points by spekcular 3y ago

SeanAnderson 3y ago
Dang :(
jitl 3y ago
The biggest question in this whole thing was, why not bring a sample to another lab for verification? Well, now we’re starting to get some reproduction attempt results anyways.
- j16sdiz 3y ago
  because they just got a few mm^3, not done experimenting with it, and was not ready to publish?
  - p-e-w 3y ago
    > because they just got a few mm^3 But why? The base materials are cheap and easily available, and the synthesis process seems rather straightforward. Why don't they have kilograms of this stuff by now?
    - adastra22 3y ago
      The synthesis process is not at all straightforward.
    - lll-o-lll 3y ago
      > synthesis process seems rather straightforward They’ve been working on this for years. To me it looks like whatever their process is, they don’t have something that’s repeatable. So maybe a couple of small samples are all there are after 1000s of attempts doing more or less the same thing.
      - p-e-w 3y ago
        So the groups trying to replicate right now are basically wasting their time?
        lll-o-lll 3y ago
        > So the groups trying to replicate right now are basically wasting their time? If a few dozen groups all try and replicate, and there is something to replicate, then odds are good someone will get lucky (birthday paradox and all that). Each individual group is definitely wasting their time, but the aggregate time spent may not be a waste.
        sophiebits 3y ago
        Birthday paradox is about random draws coinciding with each other (hence the sqrt behavior), not a target.
        lIl-IIIl 3y ago
        The birthday paradox would only apply if we are interested in one group replicating the result of any other group, not the result of the original paper. It's the difference between "do any people in this group share a birthday" vs "do any people in this group share my birthday".
        mrguyorama 3y ago
        No, this still needs replication. A room temp and pressure superconductor being possible at all, verifiably, implies there are probably better versions to be discovered. This could really improve the funding in the area, and labs that attempt replication and fail could benefit from that.
    - j16sdiz 3y ago
      These are crystals. Getting large (millimeters scale), pure crystal of the required structure is not easy. You can't do superconducting experiments on powder.
  - jitl 3y ago
    Sure but with such international intrigue maybe they can invite someone over to the lab for lunch and a quick test?
- junofan 3y ago
  > Once the findings are published in a peer-reviewed journal, which Kim says is in the works, he will support anyone who wants to create and test LK-99 for themselves. https://archive.is/DhijM https://archive.is/DhijM Maybe he’s worried it would fuck up his research pipeline?
deleted 3y ago
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kikokikokiko 3y ago
Let's hope it can be settled fast. The worse thing that can happen to a revolutionary claim like this is for it to become a "cold fusion" type of subject, with lots of "confirmations" and many more non-replications.
- jacquesm 3y ago
  That was science entirely operating as intended. What matters is the long term, not the short term dynamic.
AYBABTME 3y ago
> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. Unless we assume the original paper's authors were straight up lying, it sounds like this paper's author didn't end up with exactly the same material?
- mrandish 3y ago
  The original authors have apparently said they are only able to successfully produce the material in around 1 in 10 attempts and they don't yet know why. Also, replicators have reported that the information in the papers and the patent aren't entirely clear on some potentially significant implementation details. Unfortunately, real science makes for a pretty lousy spectator sport :-). Given the context of the release, it was always a near-certainty that early replication attempts would be a random mix of "No" and "Maybe" results. I think our best chance for any meaningful near-term clarity rest with the team of scientists reportedly visiting the original authors in their lab to test the author's own samples. While a positive result from that won't be a definitive replication, it will at least be external validation of the original process and results.
  - canjobear 3y ago
    > Unfortunately, real science makes for a pretty lousy spectator sport :-). I’ve found this whole thing incredibly entertaining and informative.
    - mrandish 3y ago
      I actually agree with you because I've enjoyed it immensely but I suspect you and I share fairly nuanced and informed perspectives. My statement was more directed to those who seem to be expecting some kind of near-term definitive verdict or box score, more like a sporting event.
      - MayeulC 3y ago
xt00 3y ago
Doesn't it seem like there should be some sort of annealing process required? this material being essentially a powder smashed into a tablet form seems like it would likely be a very poor conductor unless the superconducting properties not only existed in each of the granules of the powder, but also can easily transition between each of the boundaries. So wouldn't you want the final thing to be closer to like a ceramic form? (probably not understanding something here)
- techdragon 3y ago
  Unequivocally yes… which is why I wasn’t surprised when the first publicised reproduction involved a tiny grain, why the big pressed pellets seem to be staying put, why people are suggesting breaking the samples up, and why the original pictures/video showing the levitation that kicked all this off, is an oddly shaped sample that sort of looks like it flaked off a larger piece. Smash the samples… see if any of the grains float… (it’s becoming a bit of a refrain on Twitter whenever a big chunky pressed pellet sample is published as a failed replication) … it won’t be hard to improve the process and try and get larger contiguous samples that show the effect once we know for sure that it’s actually happening even if it’s happening in smaller more obviously superconducting samples, be it the size of a sand grain or a grain of rice, as long as it’s clearly a room temperature superconductor… once we have more samples… the analysis experts can get stuck in, there’s a global army of analytical experts… crystallographers, spectrographers, and all the sub disciplines of analytical chemistry… with clearly superconducting samples these people can swing into action and work out what the magic is and what we have to do to make more and bigger floating rocks.
  - ethbr0 3y ago
    It'll be fascinating if an industrial production process involved grinding it up, using magnets as a screen to discard non-levitating particles, then reforming the compliant ones.
- distortionfield 3y ago
  The lack of annealing seems really problematic to me
danbruc 3y ago
Maybe not yet the final nail in the coffin but I would no longer bet much on a successful replication. Which leaves me wondering how we got the initial papers. Does fraud make any sense, how could you possibly benefit from something like this? And if I would think that I might have produced a room temperature superconductor due to experimental errors, I would double and tripple check what I did. Assuming there is time for that. So incompetence? Self-delusion due to a desire for it to be true?
- dtx1 3y ago
  It seems there was a race for the patents and an early draft of the paper leaked by a researcher related (somehow) to the project.
- bestcoder69 3y ago
  Could be a skill issue on the part of the replicators? The russian anime girl scientist had to make a bunch of modifications (and was cursing the orig authors) before she could make her rocks float.
  - raincole 3y ago
    Is there any reason to treat Iris_IGB seriously? (genuine question)
  - jeron 3y ago
    >The russian anime girl scientist had to make a bunch of modifications (and was cursing the orig authors) before she could make her rocks float. link?
    - bestcoder69 3y ago
      https://twitter.com/iris_IGB/status/1685322871306928128 https://twitter.com/iris_IGB/status/1685322871306928128
      - mrguyorama 3y ago
jlaurito 3y ago
I was really confused by 'this http URL' in the abstract until I realized that arxiv.org is reading the resistance units as ohm.cm
a_vanderbilt 3y ago
Given the stark contrast in behavior between their sample and the one described in Lee et al., is this even the same material? Surely while the conductive characteristics can be explained by errors in measurement procedure, why would the behavior in a magnetic field be different? Were the original authors being dishonest? Was the replicated material different? The X-ray analysis seems to support that they are very similar, if not the same. I expect we're going to see more of this over the next week as more Chinese labs manufacture the samples.
- junofan 3y ago
  Doesn’t look like they did any annealing. Just tableting. The annealed sample was the one that levitated. Maybe that’s the issue.
  - a_vanderbilt 3y ago
    You raise a good point, that fact slipped by me in my reading of the paper. Maybe that is the problem!
p-e-w 3y ago
> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. So what about the video[1] that shows magnetic levitation occurring? Since the linked article was unable to reproduce this effect, it seems there are two possibilities: 1. The video is fake (which is really, really hard to imagine since that would predictably end the authors' careers). 2. The sample synthesized for the linked article doesn't match the original one for whatever reason. [1] https://sciencecast.org/casts/suc384jly50n https://sciencecast.org/casts/suc384jly50n
- Azrael3000 3y ago
  Apparently a new paper is supposed to come out from the original authors about the production method [0]. So it really is unclear whether everybody generates the same material. It's a shame that these papers were published before they were polished by the authors. [0] https://forums.spacebattles.com/threads/claims-of-room-temperature-and-ambient-pressure-superconductor.1106083/post-94302371 https://forums.spacebattles.com/threads/claims-of-room-tempe...
  - p-e-w 3y ago
    > It's a shame that these papers were published before they were polished by the authors. Indeed. It's also a shame that they chose to use language like: "We believe that our new development will be a brand-new historical event that opens a new era for humankind." When you make grandiose boasts like these, you better be fucking certain you are correct.
    - nonethewiser 3y ago
      You'd think they'd find a new word
      - dekhn 3y ago
        "superpressreleasing"
carabiner 3y ago
Research out of Berkeley, 1 Aug 2023: theoretical analysis suggests high-Tc superconductors from apatite possible, points to synthesis challenges. > Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key characteristics for high-TC superconductivity, namely a particularly flat isolated d-manifold, and the potential presence of fluctuating magnetism, charge and phonons. However, substitution on the other Pb(2) does not appear to have such sought-after properties, despite being the lower-energy substitution site. This result hints to the synthesis challenge in obtaining Cu substituted on the appropriate site for obtaining a bulk superconducting sample. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892 Edit: Layperson summary from https://twitter.com/Andercot/status/1686215574177841152 https://twitter.com/Andercot/status/1686215574177841152. It's crazy for the sim to not only be favorable towards SC, but also showing results that align with what the researchers proposed and what the replicators are experiencing (difficulty in synthesis). > The simulations modeled what the original Korean authors proposed was happening to their material - where copper atoms were percolating into a crystal structure and replacing lead atoms, causing the crystal to strain slightly and contract by 0.5%. This unique structure was proposed to allow this amazing property. > Lastly, these interesting conduction pathways only form when the copper atom percolates into the less likely location in the crystal lattice, or the 'higher energy' binding site. This means the material would be difficult to synthesize since only a small fraction of crystal gets its copper in just the right location.
- foota 3y ago
  Do many materials yield similar conclusions? If so, then this is just confirmation bias, but if the analysis is rare, then it might be something?
- dekhn 3y ago
  Some days I wish I could just run DFT on everything and have it spit out the ones with "interesting" results and then patent those. Unfortunately, this is not feasible (computationally) nor likely to produce very many true positives. I wonder if you could troll theorists into doing simulations of just about any substance by publishing convincing-looking papers in arxiv. Scratch that: we know it's possible.
bibabaloo 3y ago
How many days have scientists been working on this? Like 2, not including the weekend? I'm impressed that results and papers are already starting to come out.
deleted 3y ago
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ssabev 3y ago
We are so so back. Cannot wait to see the new era. Feeling real bad for the doomers
- cmrdporcupine 3y ago
  Huh? The linked paper abstract says failed to reproduce the result. And they're not the only ones: https://forums.spacebattles.com/threads/claims-of-room-temperature-and-ambient-pressure-superconductor.1106083/page-11?post=94266395#post-94266395 https://forums.spacebattles.com/threads/claims-of-room-tempe... We'll see where we are in a couple weeks, but it's not looking good.
  - tatrajim 3y ago
    They're talking about a newer paper that provides some reason for optimism. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892
schappim 3y ago
For the non-chemists/physicists: Recently[1], there was an exciting claim that a new type of material could conduct electricity perfectly at room temperature (this is what is meant by "superconductivity")[4]. This material was a version of lead-apatite [2], a type of mineral, that was altered with certain additions and made by combining two other materials, lanarkite and copper phosphide. The researchers writing this report wanted to check if this claim was true. So, they made the same types of materials (lanarkite, copper phosphide, and the altered lead-apatite) and tested how they conducted electricity and reacted to magnets. What they found was that lanarkite (Pb2SO5) didn't conduct electricity well at all, and copper phosphide Cu3P) conducted electricity similar to a semiconductor [3]. The altered lead-apatite, which was supposed to be the superconductor, behaved more like a semiconductor (a type of material that can sometimes conduct electricity, depending on conditions). Also, a key property of superconductors is that they repel magnets. But when the researchers put a magnet near their lead-apatite, there was no repulsion. Because of these tests, they're suggesting that the original claim about this room-temperature superconductor should be re-examined more carefully. It doesn't seem to behave like a superconductor in their tests. [1] https://news.ycombinator.com/item?id=36864624 https://news.ycombinator.com/item?id=36864624 [2] https://en.wikipedia.org/wiki/Apatite https://en.wikipedia.org/wiki/Apatite [3] https://en.wikipedia.org/wiki/Semiconductor https://en.wikipedia.org/wiki/Semiconductor [4] https://en.wikipedia.org/wiki/Superconductivity https://en.wikipedia.org/wiki/Superconductivity
- kumarski 3y ago
  My thoughts echoed. https://twitter.com/datarade/status/1685459221926547457?s=20 https://twitter.com/datarade/status/1685459221926547457?s=20
Mistletoe 3y ago
I get a strong feeling that this guy is like the lab that said they found life that didn’t use phosphorous for dna a few years back. I think it just turned out to be shoddy lab work and not accounting for contaminants in their lab chemicals. https://www.nature.com/articles/nature.2012.9861 https://www.nature.com/articles/nature.2012.9861 If you find something extremely rare that rewrites what we know you need to be damn sure that what you are saying is true. But some people rush to the media and trying to publish it before they’ve even made sure.
- rex_lupi 3y ago
  I mean, from the circumstances it seems quite evident they believe in what they're saying. Fyi they've been working on this material since 1999
- stefan_ 3y ago
  Good old polywater. Only this time they found something that all the scifi nerds can get excited about so the discussion is extra useless.
lucubratory 3y ago
Everyone in this thread needs to understand that particularly for materials science, and particularly when there is bad methodology documentation, it is really, really normal for early replication attempts to fail. What works in one lab will often need to be adjusted to work in another, with different equipment, altitude, humidity, all sorts of stuff. Making it even worse, apparently the original team can't even get production correct in more than 10% of runs! Combined with the slipshod methodology, doesn't this make you feel like it was silly to release the arXiv paper when they did? Well, the LK-99 team agree, according to them it was a rogue industrial scientist that they'd apparently fired four months ago who published it to arXiv with himself listed as third author. They wanted more time to nail down sample production and otherwise make a paper to their standards before release, but it effectively leaked and to avoid having credit taken from them for potentially months (or like, forever - science can be brutal) some of them decided to publish what they had on hand within a few hours. This sucks for them, a lot. I don't believe that their intention was to put out work with errors in it or incomplete methodology. Secondly, this all happened two days ago! If the methodology was perfect, I still wouldn't expect good replication results back within two (part non-business!) days. I don't know if this material is legit. I really hope it is. But the process of figuring that out could potentially take months (or more), and a two-day-later failed to replicate is not a death sentence. As much as it sucks, this is really just going to take time to prove it's not a superconductor. If it is a superconductor, we may not know for a while either, unless one of the influencers/"makers" attempting to reproduce the material succeeds and posts some good convincing video of flux pinning or other Meissner effect stuff (that person is going to go insanely viral, if it happens).
- dmvdoug 3y ago
  Not just materials science though. I’m a longtime reader of Derek Lowe’s In the Pipeline blog, and he often emphasizes the trickiness of lab work and lab techniques. But the model we have of science from elementary and high school doesn’t give us room for the random, ephemeral things that come into play in actual experimental work. Our model is methods equal result, every time, even though jiggling your foot a little bit to get the feeling back may have somehow made your small molecule production have less binding affinity or something. And yes, eventually you figure that out and stop jiggling your foot but two years have passed.
divbzero 3y ago
I’m surprised/impressed by the quick turnaround between the original LK99 paper submitted on 22 Jul 2023 and this reproduction attempt submitted on 31 Jul 2023. Could there have been a pre-print of the original paper that allowed the reproduction attempt to begin earlier?
deleted 3y ago
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ChrisCinelli 3y ago
An educated summary: https://twitter.com/Andercot/status/1686215574177841152?t=C1bZnHpYYYahHXWrpneOQA&s=19 https://twitter.com/Andercot/status/1686215574177841152?t=C1...
- classicmotto 3y ago
  this gives me hope.
alexmolas 3y ago
This is another example of why to do great science you need to do great engineering. The original group rushed to publish the paper without polishing the details, and now other groups are struggling to replicate their results.
- K5EiS 3y ago
  They didnt rush to publish it, one of them just did it without the others knowing IIRC
- NolF 3y ago
  There is apparently a whole bunch of controversy with the paper being published by one of the authors that had been allegedly kicked out and wanted to ensure he was credited as an author. The other authors were apparently still working on the paper, production methods etc but this unauthorised early publication derailed that.
awwkaw 3y ago
What they have produced is clearly not LK-99. They write that: " As shown in Figure 9, the x-ray diffraction spectrum of the ground powder of the finally sintered product is highly consistent with the x-ray diffraction spectrum reported by Lee et al.[3] and coincides well with the diffraction pattern of the apatite. This proves that we have successfully synthesized the modified lead-apatite as Lee et al.[3.4] " (First off, you need to pay to the spectrum swear jar. an XRD pattern is a pattern, not a spectrum, it resolves space, not energy.) But looking at figure 9 shows that the material is not the same. They are missing a peak at ~17.5 degrees, and have an extra one around 25 degrees. Further, all the peaks seem to be shifted about the same amount from the LK-99 structure, as the LK-99 is from pure lead-apatite. This indicates that they have an even smaller unit cell. So if the .5% compression in the original LK-99 paper is correct, there could easily be an overcompression present in this article. All the XRD pattern tells you is that they produced something wrong, an that it did not superconduct. It makes it impressive how pure the phase was in the original LK-99 paper. I will however say that there are some problems with the XRD pattern in the original paper too: They did not write which energy the XRD was measured at, one would then guess that it is Cu-Ka, but who knows. Under any circumstances, a peak should not be missing completely from a powder measurement (if it was a pellet, it could be missing due to orientation effects)
- scythe 3y ago
  I got a similar impression from the XRD spectra, but I don't think it's correct to focus on the shifts. That could easily be a minor calibration issue. The biggest difference I see is in the peak around 44 degrees, which is very pronounced in the original work and much weaker in this work. There are strong similarities between the XRD patterns, but considering the theoretical paper yesterday about selective site substitution being necessary to achieve superconductivity, it's reasonable to suspect that these "minor" differences may be critical.
jboggan 3y ago
I think this theoretical result by Griffin at the Livermore Lab explains why labs are having difficulty replicating the LK-99 sample: https://arxiv.org/pdf/2307.16892.pdf https://arxiv.org/pdf/2307.16892.pdf There are basically two repeating crystal cells. Her theoretical calculation shows superconducting properties when you substitute one cell for copper, but not the other. The "bad" substitution is a lower energy substitution that occurs more easily. "Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key characteristics for high-TC superconductivity, namely a particularly flat isolated d-manifold, and the potential presence of fluctuating magnetism, charge and phonons. However, substitution on the other Pb(2) does not appear to have such sought-after properties, despite being the lower-energy substitution site. This result hints to the synthesis challenge in obtaining Cu substituted on the appropriate site for obtaining a bulk superconducting sample."
- cthalupa 3y ago
  Her* But the paper is exciting, particularly with people now independently recreating the diamagnetic effect.
  - jboggan 3y ago
    Her*, thank you.
  - deleted 3y ago
    [deleted]
goldenarm 3y ago
[dead]
javajosh 3y ago
I was just thinking that it would be funny if, having actually discovered a high-temp ambient pressure superconductor, rather than announce it, go around to other labs and replace their samples with yours.
redm 3y ago
Seems there is new support that its legit! https://twitter.com/Andercot/status/1686215574177841152 https://twitter.com/Andercot/status/1686215574177841152 National Lab (LBNL) results support LK-99 as a room-temperature ambient-pressure superconductor. Simulations published 1 hour ago on arxiv support LK-99 as the holy grail of modern material science and applied physics. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892
- FredFS456 3y ago
  HN thread on this preprint: https://news.ycombinator.com/item?id=36951815 https://news.ycombinator.com/item?id=36951815
- whimsicalism 3y ago
  I worked in this field and imo these preliminary DFT results do not actually mean that much. I do not believe the comments on that other thread are from other practitioners given how confident in this DFT results they seem, when DFT is notoriously unreliable especially when funky correlated things might be going on.
  - carabiner 3y ago
    Yes CMTC has said that this preprint changes nothing. The author's mic drop gif is a bit... premature.
  - fnands 3y ago
    Yeah, I would class it as encouraging, but far from definitive. But at least it shows that there might be some theoretical basis to it. It might be useful (as jboggan mentioned in another thread) in explaining why reproduction could be difficult; it seems to be a finicky material to create.
    - whimsicalism 3y ago
      Oh yes, I also don’t think this reproduction failure is a strong signal either. It is super finicky usually in practice
shireboy 3y ago
A little bit of a rabbit trail, but with this and similar science/reporting issues, I find myself wishing both the hype and the vitriol was taken out completely. What if the world could follow the LK-99 team and replication attempts in near real time and everyone had a sense like "if this succeeds, great, if not, we know one more way it doesn't work". And what if the millions of various studies on any topic were publicly accessible, instantly searchable, discussed intelligently, then novel ideas bubbled up and became studies themselves. I understand I'm being naive here and ignoring "little" things like funding, profit motives, and basic human nature. But more what I'm suggesting is that there has to be a way to speed up scientific research and application while toning down the hyperbole. This really became apparent to me during Covid. There _have_ to be ways to rethink from first principles how we do and report on science.
- erlich 3y ago
  It's amazing we don't have good personal content filtering yet. I would pay so much for an all-encompassing blocker. There is so much content I would block if I actually could. Completely disable YouTube Shorts on mobile. All snarky/sarcastic/political/ad-hominem takes filtered.
  - dasv 3y ago
    There is an interesting take on this on Neal Stephenson's Termination Shock: wealthy people can afford to have personal curators that filter news and other content for them, while the lower classes have been driven off the deep end by the near future Internet's relentless stream of disinformation.
fallingfrog 3y ago
I had a feeling this is what was going on. None of the videos were very convincing.
alangibson 3y ago
A paper dropped on the 29th examining if their theory of LK99's superconducting mechanism was plausible. The good news that it is. The bad news is that the copper atoms need to end up in the least likely place in the crystal. Long story short, though the ingredients are easy to find we should expect reproduction to take longer than we first thought.
dgdosen 3y ago
Can anyone ELI5 - Is the compound/material used for LK-99 that unique? Are there other, similar materials that might also have this 'quantum well' quality?
- BizarroLand 3y ago
  It's relatively common materials, basically, lead, copper, sulfur, and oxygen, combined in a specific manner. There is a chance that either the original measurements were wrong or that there remains some unrealized step in the process to make the superconductor superconduct.

613 points by spekcular 3y ago

Dang :(

jitl 3y ago

The biggest question in this whole thing was, why not bring a sample to another lab for verification? Well, now we’re starting to get some reproduction attempt results anyways.

j16sdiz 3y ago
because they just got a few mm^3, not done experimenting with it, and was not ready to publish?
- p-e-w 3y ago
  > because they just got a few mm^3 But why? The base materials are cheap and easily available, and the synthesis process seems rather straightforward. Why don't they have kilograms of this stuff by now?
  - adastra22 3y ago
    The synthesis process is not at all straightforward.
  - lll-o-lll 3y ago
    > synthesis process seems rather straightforward They’ve been working on this for years. To me it looks like whatever their process is, they don’t have something that’s repeatable. So maybe a couple of small samples are all there are after 1000s of attempts doing more or less the same thing.
    - p-e-w 3y ago
      So the groups trying to replicate right now are basically wasting their time?
      - lll-o-lll 3y ago
        > So the groups trying to replicate right now are basically wasting their time? If a few dozen groups all try and replicate, and there is something to replicate, then odds are good someone will get lucky (birthday paradox and all that). Each individual group is definitely wasting their time, but the aggregate time spent may not be a waste.
        sophiebits 3y ago
        Birthday paradox is about random draws coinciding with each other (hence the sqrt behavior), not a target.
        lIl-IIIl 3y ago
        The birthday paradox would only apply if we are interested in one group replicating the result of any other group, not the result of the original paper. It's the difference between "do any people in this group share a birthday" vs "do any people in this group share my birthday".
      - mrguyorama 3y ago
        No, this still needs replication. A room temp and pressure superconductor being possible at all, verifiably, implies there are probably better versions to be discovered. This could really improve the funding in the area, and labs that attempt replication and fail could benefit from that.
  - j16sdiz 3y ago
    These are crystals. Getting large (millimeters scale), pure crystal of the required structure is not easy. You can't do superconducting experiments on powder.
- jitl 3y ago
  Sure but with such international intrigue maybe they can invite someone over to the lab for lunch and a quick test?
junofan 3y ago
> Once the findings are published in a peer-reviewed journal, which Kim says is in the works, he will support anyone who wants to create and test LK-99 for themselves. https://archive.is/DhijM https://archive.is/DhijM Maybe he’s worried it would fuck up his research pipeline?

deleted 3y ago

[deleted]

kikokikokiko 3y ago

Let's hope it can be settled fast. The worse thing that can happen to a revolutionary claim like this is for it to become a "cold fusion" type of subject, with lots of "confirmations" and many more non-replications.

jacquesm 3y ago
That was science entirely operating as intended. What matters is the long term, not the short term dynamic.

AYBABTME 3y ago

> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. Unless we assume the original paper's authors were straight up lying, it sounds like this paper's author didn't end up with exactly the same material?

mrandish 3y ago
The original authors have apparently said they are only able to successfully produce the material in around 1 in 10 attempts and they don't yet know why. Also, replicators have reported that the information in the papers and the patent aren't entirely clear on some potentially significant implementation details. Unfortunately, real science makes for a pretty lousy spectator sport :-). Given the context of the release, it was always a near-certainty that early replication attempts would be a random mix of "No" and "Maybe" results. I think our best chance for any meaningful near-term clarity rest with the team of scientists reportedly visiting the original authors in their lab to test the author's own samples. While a positive result from that won't be a definitive replication, it will at least be external validation of the original process and results.
- canjobear 3y ago
  > Unfortunately, real science makes for a pretty lousy spectator sport :-). I’ve found this whole thing incredibly entertaining and informative.
  - mrandish 3y ago
    I actually agree with you because I've enjoyed it immensely but I suspect you and I share fairly nuanced and informed perspectives. My statement was more directed to those who seem to be expecting some kind of near-term definitive verdict or box score, more like a sporting event.
    - MayeulC 3y ago

xt00 3y ago

Doesn't it seem like there should be some sort of annealing process required? this material being essentially a powder smashed into a tablet form seems like it would likely be a very poor conductor unless the superconducting properties not only existed in each of the granules of the powder, but also can easily transition between each of the boundaries. So wouldn't you want the final thing to be closer to like a ceramic form? (probably not understanding something here)

techdragon 3y ago
Unequivocally yes… which is why I wasn’t surprised when the first publicised reproduction involved a tiny grain, why the big pressed pellets seem to be staying put, why people are suggesting breaking the samples up, and why the original pictures/video showing the levitation that kicked all this off, is an oddly shaped sample that sort of looks like it flaked off a larger piece. Smash the samples… see if any of the grains float… (it’s becoming a bit of a refrain on Twitter whenever a big chunky pressed pellet sample is published as a failed replication) … it won’t be hard to improve the process and try and get larger contiguous samples that show the effect once we know for sure that it’s actually happening even if it’s happening in smaller more obviously superconducting samples, be it the size of a sand grain or a grain of rice, as long as it’s clearly a room temperature superconductor… once we have more samples… the analysis experts can get stuck in, there’s a global army of analytical experts… crystallographers, spectrographers, and all the sub disciplines of analytical chemistry… with clearly superconducting samples these people can swing into action and work out what the magic is and what we have to do to make more and bigger floating rocks.
- ethbr0 3y ago
  It'll be fascinating if an industrial production process involved grinding it up, using magnets as a screen to discard non-levitating particles, then reforming the compliant ones.
distortionfield 3y ago
The lack of annealing seems really problematic to me

danbruc 3y ago

Maybe not yet the final nail in the coffin but I would no longer bet much on a successful replication. Which leaves me wondering how we got the initial papers. Does fraud make any sense, how could you possibly benefit from something like this? And if I would think that I might have produced a room temperature superconductor due to experimental errors, I would double and tripple check what I did. Assuming there is time for that. So incompetence? Self-delusion due to a desire for it to be true?

dtx1 3y ago
It seems there was a race for the patents and an early draft of the paper leaked by a researcher related (somehow) to the project.
bestcoder69 3y ago
Could be a skill issue on the part of the replicators? The russian anime girl scientist had to make a bunch of modifications (and was cursing the orig authors) before she could make her rocks float.
- raincole 3y ago
  Is there any reason to treat Iris_IGB seriously? (genuine question)
- jeron 3y ago
  >The russian anime girl scientist had to make a bunch of modifications (and was cursing the orig authors) before she could make her rocks float. link?
  - bestcoder69 3y ago
    https://twitter.com/iris_IGB/status/1685322871306928128 https://twitter.com/iris_IGB/status/1685322871306928128
    - mrguyorama 3y ago

jlaurito 3y ago

I was really confused by 'this http URL' in the abstract until I realized that arxiv.org is reading the resistance units as ohm.cm

a_vanderbilt 3y ago

Given the stark contrast in behavior between their sample and the one described in Lee et al., is this even the same material? Surely while the conductive characteristics can be explained by errors in measurement procedure, why would the behavior in a magnetic field be different? Were the original authors being dishonest? Was the replicated material different? The X-ray analysis seems to support that they are very similar, if not the same. I expect we're going to see more of this over the next week as more Chinese labs manufacture the samples.

junofan 3y ago
Doesn’t look like they did any annealing. Just tableting. The annealed sample was the one that levitated. Maybe that’s the issue.
- a_vanderbilt 3y ago
  You raise a good point, that fact slipped by me in my reading of the paper. Maybe that is the problem!

p-e-w 3y ago

> In addition, when a pressed Pb10-xCux(PO4)6O pellet is located on top of a commercial Nd2Fe14B magnet at room temperature, no repulsion could be felt and no magnetic levitation was observed either. So what about the video[1] that shows magnetic levitation occurring? Since the linked article was unable to reproduce this effect, it seems there are two possibilities: 1. The video is fake (which is really, really hard to imagine since that would predictably end the authors' careers). 2. The sample synthesized for the linked article doesn't match the original one for whatever reason. [1] https://sciencecast.org/casts/suc384jly50n https://sciencecast.org/casts/suc384jly50n

Azrael3000 3y ago
Apparently a new paper is supposed to come out from the original authors about the production method [0]. So it really is unclear whether everybody generates the same material. It's a shame that these papers were published before they were polished by the authors. [0] https://forums.spacebattles.com/threads/claims-of-room-temperature-and-ambient-pressure-superconductor.1106083/post-94302371 https://forums.spacebattles.com/threads/claims-of-room-tempe...
- p-e-w 3y ago
  > It's a shame that these papers were published before they were polished by the authors. Indeed. It's also a shame that they chose to use language like: "We believe that our new development will be a brand-new historical event that opens a new era for humankind." When you make grandiose boasts like these, you better be fucking certain you are correct.
  - nonethewiser 3y ago
    You'd think they'd find a new word
    - dekhn 3y ago
      "superpressreleasing"

carabiner 3y ago

Research out of Berkeley, 1 Aug 2023: theoretical analysis suggests high-Tc superconductors from apatite possible, points to synthesis challenges. > Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key characteristics for high-TC superconductivity, namely a particularly flat isolated d-manifold, and the potential presence of fluctuating magnetism, charge and phonons. However, substitution on the other Pb(2) does not appear to have such sought-after properties, despite being the lower-energy substitution site. This result hints to the synthesis challenge in obtaining Cu substituted on the appropriate site for obtaining a bulk superconducting sample. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892 Edit: Layperson summary from https://twitter.com/Andercot/status/1686215574177841152 https://twitter.com/Andercot/status/1686215574177841152. It's crazy for the sim to not only be favorable towards SC, but also showing results that align with what the researchers proposed and what the replicators are experiencing (difficulty in synthesis). > The simulations modeled what the original Korean authors proposed was happening to their material - where copper atoms were percolating into a crystal structure and replacing lead atoms, causing the crystal to strain slightly and contract by 0.5%. This unique structure was proposed to allow this amazing property. > Lastly, these interesting conduction pathways only form when the copper atom percolates into the less likely location in the crystal lattice, or the 'higher energy' binding site. This means the material would be difficult to synthesize since only a small fraction of crystal gets its copper in just the right location.

foota 3y ago
Do many materials yield similar conclusions? If so, then this is just confirmation bias, but if the analysis is rare, then it might be something?
dekhn 3y ago
Some days I wish I could just run DFT on everything and have it spit out the ones with "interesting" results and then patent those. Unfortunately, this is not feasible (computationally) nor likely to produce very many true positives. I wonder if you could troll theorists into doing simulations of just about any substance by publishing convincing-looking papers in arxiv. Scratch that: we know it's possible.

bibabaloo 3y ago

How many days have scientists been working on this? Like 2, not including the weekend? I'm impressed that results and papers are already starting to come out.

deleted 3y ago

[deleted]

ssabev 3y ago

We are so so back. Cannot wait to see the new era. Feeling real bad for the doomers

cmrdporcupine 3y ago
Huh? The linked paper abstract says failed to reproduce the result. And they're not the only ones: https://forums.spacebattles.com/threads/claims-of-room-temperature-and-ambient-pressure-superconductor.1106083/page-11?post=94266395#post-94266395 https://forums.spacebattles.com/threads/claims-of-room-tempe... We'll see where we are in a couple weeks, but it's not looking good.
- tatrajim 3y ago
  They're talking about a newer paper that provides some reason for optimism. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892

schappim 3y ago

For the non-chemists/physicists: Recently[1], there was an exciting claim that a new type of material could conduct electricity perfectly at room temperature (this is what is meant by "superconductivity")[4]. This material was a version of lead-apatite [2], a type of mineral, that was altered with certain additions and made by combining two other materials, lanarkite and copper phosphide. The researchers writing this report wanted to check if this claim was true. So, they made the same types of materials (lanarkite, copper phosphide, and the altered lead-apatite) and tested how they conducted electricity and reacted to magnets. What they found was that lanarkite (Pb2SO5) didn't conduct electricity well at all, and copper phosphide Cu3P) conducted electricity similar to a semiconductor [3]. The altered lead-apatite, which was supposed to be the superconductor, behaved more like a semiconductor (a type of material that can sometimes conduct electricity, depending on conditions). Also, a key property of superconductors is that they repel magnets. But when the researchers put a magnet near their lead-apatite, there was no repulsion. Because of these tests, they're suggesting that the original claim about this room-temperature superconductor should be re-examined more carefully. It doesn't seem to behave like a superconductor in their tests. [1] https://news.ycombinator.com/item?id=36864624 https://news.ycombinator.com/item?id=36864624 [2] https://en.wikipedia.org/wiki/Apatite https://en.wikipedia.org/wiki/Apatite [3] https://en.wikipedia.org/wiki/Semiconductor https://en.wikipedia.org/wiki/Semiconductor [4] https://en.wikipedia.org/wiki/Superconductivity https://en.wikipedia.org/wiki/Superconductivity

kumarski 3y ago
My thoughts echoed. https://twitter.com/datarade/status/1685459221926547457?s=20 https://twitter.com/datarade/status/1685459221926547457?s=20

Mistletoe 3y ago

I get a strong feeling that this guy is like the lab that said they found life that didn’t use phosphorous for dna a few years back. I think it just turned out to be shoddy lab work and not accounting for contaminants in their lab chemicals. https://www.nature.com/articles/nature.2012.9861 https://www.nature.com/articles/nature.2012.9861 If you find something extremely rare that rewrites what we know you need to be damn sure that what you are saying is true. But some people rush to the media and trying to publish it before they’ve even made sure.

rex_lupi 3y ago
I mean, from the circumstances it seems quite evident they believe in what they're saying. Fyi they've been working on this material since 1999
stefan_ 3y ago
Good old polywater. Only this time they found something that all the scifi nerds can get excited about so the discussion is extra useless.

lucubratory 3y ago

Everyone in this thread needs to understand that particularly for materials science, and particularly when there is bad methodology documentation, it is really, really normal for early replication attempts to fail. What works in one lab will often need to be adjusted to work in another, with different equipment, altitude, humidity, all sorts of stuff. Making it even worse, apparently the original team can't even get production correct in more than 10% of runs! Combined with the slipshod methodology, doesn't this make you feel like it was silly to release the arXiv paper when they did? Well, the LK-99 team agree, according to them it was a rogue industrial scientist that they'd apparently fired four months ago who published it to arXiv with himself listed as third author. They wanted more time to nail down sample production and otherwise make a paper to their standards before release, but it effectively leaked and to avoid having credit taken from them for potentially months (or like, forever - science can be brutal) some of them decided to publish what they had on hand within a few hours. This sucks for them, a lot. I don't believe that their intention was to put out work with errors in it or incomplete methodology. Secondly, this all happened two days ago! If the methodology was perfect, I still wouldn't expect good replication results back within two (part non-business!) days. I don't know if this material is legit. I really hope it is. But the process of figuring that out could potentially take months (or more), and a two-day-later failed to replicate is not a death sentence. As much as it sucks, this is really just going to take time to prove it's not a superconductor. If it is a superconductor, we may not know for a while either, unless one of the influencers/"makers" attempting to reproduce the material succeeds and posts some good convincing video of flux pinning or other Meissner effect stuff (that person is going to go insanely viral, if it happens).

dmvdoug 3y ago
Not just materials science though. I’m a longtime reader of Derek Lowe’s In the Pipeline blog, and he often emphasizes the trickiness of lab work and lab techniques. But the model we have of science from elementary and high school doesn’t give us room for the random, ephemeral things that come into play in actual experimental work. Our model is methods equal result, every time, even though jiggling your foot a little bit to get the feeling back may have somehow made your small molecule production have less binding affinity or something. And yes, eventually you figure that out and stop jiggling your foot but two years have passed.

divbzero 3y ago

I’m surprised/impressed by the quick turnaround between the original LK99 paper submitted on 22 Jul 2023 and this reproduction attempt submitted on 31 Jul 2023. Could there have been a pre-print of the original paper that allowed the reproduction attempt to begin earlier?

deleted 3y ago

[deleted]

ChrisCinelli 3y ago

An educated summary: https://twitter.com/Andercot/status/1686215574177841152?t=C1bZnHpYYYahHXWrpneOQA&s=19 https://twitter.com/Andercot/status/1686215574177841152?t=C1...

classicmotto 3y ago
this gives me hope.

alexmolas 3y ago

This is another example of why to do great science you need to do great engineering. The original group rushed to publish the paper without polishing the details, and now other groups are struggling to replicate their results.

K5EiS 3y ago
They didnt rush to publish it, one of them just did it without the others knowing IIRC
NolF 3y ago
There is apparently a whole bunch of controversy with the paper being published by one of the authors that had been allegedly kicked out and wanted to ensure he was credited as an author. The other authors were apparently still working on the paper, production methods etc but this unauthorised early publication derailed that.

awwkaw 3y ago

What they have produced is clearly not LK-99. They write that: " As shown in Figure 9, the x-ray diffraction spectrum of the ground powder of the finally sintered product is highly consistent with the x-ray diffraction spectrum reported by Lee et al.[3] and coincides well with the diffraction pattern of the apatite. This proves that we have successfully synthesized the modified lead-apatite as Lee et al.[3.4] " (First off, you need to pay to the spectrum swear jar. an XRD pattern is a pattern, not a spectrum, it resolves space, not energy.) But looking at figure 9 shows that the material is not the same. They are missing a peak at ~17.5 degrees, and have an extra one around 25 degrees. Further, all the peaks seem to be shifted about the same amount from the LK-99 structure, as the LK-99 is from pure lead-apatite. This indicates that they have an even smaller unit cell. So if the .5% compression in the original LK-99 paper is correct, there could easily be an overcompression present in this article. All the XRD pattern tells you is that they produced something wrong, an that it did not superconduct. It makes it impressive how pure the phase was in the original LK-99 paper. I will however say that there are some problems with the XRD pattern in the original paper too: They did not write which energy the XRD was measured at, one would then guess that it is Cu-Ka, but who knows. Under any circumstances, a peak should not be missing completely from a powder measurement (if it was a pellet, it could be missing due to orientation effects)

scythe 3y ago
I got a similar impression from the XRD spectra, but I don't think it's correct to focus on the shifts. That could easily be a minor calibration issue. The biggest difference I see is in the peak around 44 degrees, which is very pronounced in the original work and much weaker in this work. There are strong similarities between the XRD patterns, but considering the theoretical paper yesterday about selective site substitution being necessary to achieve superconductivity, it's reasonable to suspect that these "minor" differences may be critical.

jboggan 3y ago

I think this theoretical result by Griffin at the Livermore Lab explains why labs are having difficulty replicating the LK-99 sample: https://arxiv.org/pdf/2307.16892.pdf https://arxiv.org/pdf/2307.16892.pdf There are basically two repeating crystal cells. Her theoretical calculation shows superconducting properties when you substitute one cell for copper, but not the other. The "bad" substitution is a lower energy substitution that occurs more easily. "Finally, the calculations presented here suggest that Cu substitution on the appropriate (Pb(1)) site displays many key characteristics for high-TC superconductivity, namely a particularly flat isolated d-manifold, and the potential presence of fluctuating magnetism, charge and phonons. However, substitution on the other Pb(2) does not appear to have such sought-after properties, despite being the lower-energy substitution site. This result hints to the synthesis challenge in obtaining Cu substituted on the appropriate site for obtaining a bulk superconducting sample."

cthalupa 3y ago
Her* But the paper is exciting, particularly with people now independently recreating the diamagnetic effect.
- jboggan 3y ago
  Her*, thank you.
- deleted 3y ago
  [deleted]

goldenarm 3y ago

[dead]

javajosh 3y ago

I was just thinking that it would be funny if, having actually discovered a high-temp ambient pressure superconductor, rather than announce it, go around to other labs and replace their samples with yours.

redm 3y ago

Seems there is new support that its legit! https://twitter.com/Andercot/status/1686215574177841152 https://twitter.com/Andercot/status/1686215574177841152 National Lab (LBNL) results support LK-99 as a room-temperature ambient-pressure superconductor. Simulations published 1 hour ago on arxiv support LK-99 as the holy grail of modern material science and applied physics. https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892

FredFS456 3y ago
HN thread on this preprint: https://news.ycombinator.com/item?id=36951815 https://news.ycombinator.com/item?id=36951815
whimsicalism 3y ago
I worked in this field and imo these preliminary DFT results do not actually mean that much. I do not believe the comments on that other thread are from other practitioners given how confident in this DFT results they seem, when DFT is notoriously unreliable especially when funky correlated things might be going on.
- carabiner 3y ago
  Yes CMTC has said that this preprint changes nothing. The author's mic drop gif is a bit... premature.
- fnands 3y ago
  Yeah, I would class it as encouraging, but far from definitive. But at least it shows that there might be some theoretical basis to it. It might be useful (as jboggan mentioned in another thread) in explaining why reproduction could be difficult; it seems to be a finicky material to create.
  - whimsicalism 3y ago
    Oh yes, I also don’t think this reproduction failure is a strong signal either. It is super finicky usually in practice

shireboy 3y ago

A little bit of a rabbit trail, but with this and similar science/reporting issues, I find myself wishing both the hype and the vitriol was taken out completely. What if the world could follow the LK-99 team and replication attempts in near real time and everyone had a sense like "if this succeeds, great, if not, we know one more way it doesn't work". And what if the millions of various studies on any topic were publicly accessible, instantly searchable, discussed intelligently, then novel ideas bubbled up and became studies themselves. I understand I'm being naive here and ignoring "little" things like funding, profit motives, and basic human nature. But more what I'm suggesting is that there has to be a way to speed up scientific research and application while toning down the hyperbole. This really became apparent to me during Covid. There _have_ to be ways to rethink from first principles how we do and report on science.

erlich 3y ago
It's amazing we don't have good personal content filtering yet. I would pay so much for an all-encompassing blocker. There is so much content I would block if I actually could. Completely disable YouTube Shorts on mobile. All snarky/sarcastic/political/ad-hominem takes filtered.
- dasv 3y ago
  There is an interesting take on this on Neal Stephenson's Termination Shock: wealthy people can afford to have personal curators that filter news and other content for them, while the lower classes have been driven off the deep end by the near future Internet's relentless stream of disinformation.

fallingfrog 3y ago

I had a feeling this is what was going on. None of the videos were very convincing.

alangibson 3y ago

A paper dropped on the 29th examining if their theory of LK99's superconducting mechanism was plausible. The good news that it is. The bad news is that the copper atoms need to end up in the least likely place in the crystal. Long story short, though the ingredients are easy to find we should expect reproduction to take longer than we first thought.

dgdosen 3y ago

Can anyone ELI5 - Is the compound/material used for LK-99 that unique? Are there other, similar materials that might also have this 'quantum well' quality?

BizarroLand 3y ago
It's relatively common materials, basically, lead, copper, sulfur, and oxygen, combined in a specific manner. There is a chance that either the original measurements were wrong or that there remains some unrealized step in the process to make the superconductor superconduct.