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Room-Temperature Ambient-Pressure Superconductor LK-99 preprint revision 2
- lifthrasiir 3y agotl;dr: The only change, aside from the increased number of broken bookmarks, is that the misleading Fig. 4a in the page 7 has been splitted into Fig. 4a and 4b with different axes.
- sanxiyn 3y agoWhat's up with "Error! Bookmark not defined"? Is this some kind of trolling? I guess its presence in the first version is understandable if it was posted in hurry, but why leave it in the revised version?
- layer8 3y agoThis can happen when saving a Word document as PDF. You don’t see it in the Word document before, but it ends up that way in the PDF. They apparently didn’t double-check the PDF.
- joefigura 3y agoI just wrote a comment in another thread that's relevant here too. It looks like the first superconductor paper was released by a rouge researcher, without the agreement of the other two authors or the rest of the LK-99 group. This forced the LK-99 group to rush to publish the official paper, with a cost to quality. The LK-99 group released v2 a week later (on Saturday), and probably will continue to update it. A premature release explains many of the oddities about the two papers The first paper submitted is titled "The First Room-Temperature Ambient-Pressure Superconductor." It lists three authors: Sukbae Lee, Ji-Hoon Kim, and Young-Wan Kwon. Its timestamp is Saturday, July 22, 2023 at 07:51:19 UTC. [1] The second paper submitted is titled "Superconductor Pb10−xCux(PO4)6O showing levitation at room temperature and atmospheric pressure and mechanism." This paper lists six authors: Sukbae Lee, Jihoon Kim, Hyun-Tak Kim, Sungyeon Im, SooMin An, Keun Ho Auh [2]. Its timestamp is Saturday, July 22nd, 2023 at 10:11:28 UTC, or two hours and twenty minutes after the first paper. The second paper was updated a week later, on Saturday, July 29, 2023 at 01:53:47 UTC, In both papers the first author is Sukbae Lee and the second author is Jihoon Kim, and in both their affiliation is given as "Quantum Energy Research center, Inc." in Seoul. The first paper posted has Young-Wan Kwon as third author. The second paper does not have Young-Wan Kwon as an author, and has four additional authors with various affiliations. The second paper appears to have been was prepared in LaTeX, and the first paper appears to have been prepared in Word. The title and abstract of the first paper explicitly claim LK-99 is a room temperature superconductor. The title and abstract of the second paper don't explicitly claim that, though to me some of their terminology suggest LK-99 is a superconductor. The accusation in [3] is that Young-Wan Kwon published the first paper without the consent of the rest of the LK-99 team, listed himself as third author, and left off the other four authors. The rest of the LK-99 team rushed to stuff what they had into the second paper, and released it 2 hours later [4]. This explains why there are two different papers from the same group submitted on the same day, it explains why the author lists are different between the two, and it explains why the second paper and not the first has been updated. I'm not in the field and have only read each paper once, so I'm not certain, but I'm betting it also explains a lot of the mistakes and messy bits of the papers. This makes cautiously optimistic that this might be for real [5]. The papers on arXiv as of Monday night are consistent with a research group that succeeded in producing and identifying a room temperature superconductor using a fabrication process that is a bit tricky, and who were then forced to publish prematurely. There's nowhere near enough evidence to conclude LK-99 is a room temperature superconductor. But one failed replication doesn't prove LK-99 isn't a superconductor - if the fabrication process is finicky we'd expect to see a few dozen failed reproductions and a few successful reproductions. Edit: Here's an appendix to bring us up to date to Monday night U.S. time. Two additional papers have been published in response to the LK-99 claims, for a total of four. The 3rd paper is an unsuccessful attempt to reproduce the LK-99 group's results experimentally. It is titled "Semiconducting transport in Pb10-xCux(PO4)6O sintered from Pb2SO5 and Cu3P." 9 authors, all affiliated with the Materials Science department of Beihang University in Beijing. Timestamp Monday July 31st at 16:13:05 UTC. [6] The fourth paper is a set of simulations of LK-99 that observes some similarities between LK-99 and other materials that are high-temperature superconductors. It is titled "Origin of correlated isolated flat bands in copper-substituted lead phosphate apatite." A single author, who is affiliated with Materials Science at Lawrence Berkeley National Lab in California. Published on Monday, July 31st, 2023 at 17:58:17 UTC. [7] [1] https://arxiv.org/abs/2307.12008 https://arxiv.org/abs/2307.12008 [2] https://arxiv.org/abs/2307.12037 https://arxiv.org/abs/2307.12037 [3] This comment was originally written in reply to: https://news.ycombinator.com/item?id=36952499 https://news.ycombinator.com/item?id=36952499 [4] Though I don't think we know publicly whether the all authors agreed to publish the second paper, either. It seems equally plausible that some portion of the group rushed to publish, or even that one author published it independently. [5] And by cautiously optimistic, I really mean "extremely excited and nervous, enough to stay up until 3am collating arXiv timestamps" [6] arXiv link: https://arxiv.org/abs/2307.16802 https://arxiv.org/abs/2307.16802 HN link": https://news.ycombinator.com/item?id=36951140 https://news.ycombinator.com/item?id=36951140 [7] arXiv: https://arxiv.org/abs/2307.16892 https://arxiv.org/abs/2307.16892 HN: https://news.ycombinator.com/item?id=36951815 https://news.ycombinator.com/item?id=36951815
- BlueTemplar 3y agoThey are only preprints anyway, it's not like they matter ? No peer review, and it's not like the preprints are going to matter much compared to the lab evidence for claims of discovery ?
- was_a_dev 3y agoIt is suggested that politics has come into play here as only three people can win a Nobel Prize. I hope that, if this ends in a Nobel Prize, that "sportsmanship" comes into account
- est 3y agoIf LK-99 is true, Nobel Prize should make an exception for all the authors.
- jeffwass 3y agoWhy does this particular discovery merit an exception, but every other Nobel does not?
- r2_pilot 3y agoPerhaps with all the lower-hanging scientific fruit now getting more scarce, it makes sense to start allowing for a larger number of contributors to be recognized, even if they don't necessarily share in the prize money. Why not start such a new tradition when such a practical and wide-ranging technology comes into play? (assuming this is eventually validated)
- calderknight 3y agowould then make sense to award the prize less frequently
- rapsey 3y agoBecause if true it will be the most important discovery of this century?
- brunooliv 3y agoWhat are the implications in general of room temperature superconductors? I just know that they needed typically ultra low temperatures right? But what would be the practical implications?
- bibabaloo 3y agoThis thread covers some: https://twitter.com/Andercot/status/1685088625187495936 https://twitter.com/Andercot/status/1685088625187495936
- asimpletune 3y agoThe battery one is crazy, where you just store the electrons in a loop.
- aqme28 3y agoYou're basically storing your energy as magnetic potential. Pretty neat.
- XCSme 3y agoBut how do you get them out? Don't electrons prefer the path of least resistance, so that is staying in the superconductor? Or they won't stand still?
- jesse9766 3y agoConverting magnetic force into electrical current (electromagnetic induction) is the principal behind of all electrical power generation. SMES (superconducting magnetic electrical storage) is essentially an inductor made using superconductors. Electrical current gets converted into magnetic force and then back into electrical current when the circuit is discharged.
- XCSme 3y agoSo they still generate permanent electromagnetic force when "charged"?
- sonium 3y agoI have a PhD in material science and worked with superconductors, here are two things that is often misunderstood: 1) it takes a undergrad to make and measure a superconductor but a Nobel laureate to explain it. 2) in theory if you understand the mechanism of something you can improve it. In material science however almost always all you need is a trial and error approach to end up with a good result. Conclusion: the effect is probably true, the explanation not edit: typo
- huijzer 3y ago> 1) it takes a undergrad to make and measure a superconductor by a Nobel laureate to explain it. Another example of Taleb’s idea that experimentation comes first and theories second. Universities pretend that it’s the other way around but apart from an Einstein it’s usually not.
- anonymous_sorry 3y agoIt's a feedback loop. Experimental results suggest new theories, which suggest new experiments to test those theories.
- johndunne 3y agoWell put. I'd add that theories can produce predictions, and if the predictions can be proved experimentally, all the better for the theory.
- anonymous_sorry 3y agoOr perhaps even stronger - theories _should_ produce predictions.
- mrguyorama 3y agoAny theory that cannot make a prediction isn't a theory but rather a data compression method.
- est 3y agohttps://www.bilibili.com/video/BV14p4y1V7kS/ https://www.bilibili.com/video/BV14p4y1V7kS/ Latest update: the diamagnetism has been confirmed from a tiny LK-99 replica sample. The Author posted: > Under the guidance of Professor Haixin Chang, postdoctor Hao Wu and PhD student Li Yang from the School of Materials Science and Technology of Huazhong University of Science and Technology successfully for the first time verified the LK-99 crystal that can be magnetically levitated with larger levitated angle than Sukbae Lee‘s sample at room temperature. It is expected to realize the true potential of room temperature, non-contact superconducting magnetic levitation. Update: second video showing it's not paramagnetic https://www.bilibili.com/video/BV13k4y1G7i1/ https://www.bilibili.com/video/BV13k4y1G7i1/
- anotheryou 3y agolove the atomic full screen button on the video player XD
- smcameron 3y agoBetter than the WWII era German aircraft insignia youtube uses for the "unfullscreen" button.
- mcpackieh 3y agoDon't look up the Bundeswehr, I'm not sure you could handle the shock.
- xdennis 3y agoHa, it really does look like the Balkenkreuz[1]. Although it was in use before Hitler and it's just a cross. [1]: https://en.wikipedia.org/wiki/Balkenkreuz https://en.wikipedia.org/wiki/Balkenkreuz
- smcameron 3y agoThanks, I knew there had to be a name for that thing, now I know what it is.
- ly3xqhl8g9 3y ago"In no case may a prize amount be divided between more than three persons." [1] Sad state of affairs to expect a reward for brilliance and to have science bottlenecked by a merchant of death. Just the fact that the merchant of death gives "peace prizes" should have made the entire affair laughable a long time ago. Perhaps it's time to move on from this ancient and limited understanding of appraisal, awards. I'm in no position to ever receive a Nobel prize, but I'm fairly certain I am moral enough to reject such a grandstanding award coming from such a troubled tradition. Yes, I just virtue-signalled calling immoral every recipient of the Nobel Prize, mostly out of sheer distaste for the ceremony, but also thinking of the terrible inefficiency which has plagued science and research in the last 122 years. How many discoveries were missed because following the course to unveil them was not "Nobel-worthy". How many scientists had their careers ruined for pursuing the Nobel award without being granted anything. Just the fact that only 1.8% of the Nobel Prize in Physics were awarded to women [2] shows the entire thing as the charade it is, no other context needed. [1] https://www.nobelprize.org/frequently-asked-questions/#:~:text=%E2%80%9CIn%20no%20case%20may%20a%20prize%20amount%20be%20divided%20between%20more%20than%20three%20persons.%E2%80%9D%E2%80%AF https://www.nobelprize.org/frequently-asked-questions/#:~:te... [2] https://en.wikipedia.org/wiki/List_of_female_Nobel_laureates https://en.wikipedia.org/wiki/List_of_female_Nobel_laureates
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- ajb117 3y agoI don't know much physics, but is there a reason we should be hoping for superconductivity specifically rather than a cheap material that's just a very very good conductor? Also, even if LK-99 were superconductive, that wouldn't imply it would be useful for computing, right? Surely there are materials that are better conductors than silicon but have mechanical and other physical quirks preventing us from using then for chips.
- clarionbell 3y agoThere is a lot more than just silicon wafers in our computers. Let's start with all those traces on board. Right now they are made of copper. But what if they could conduct with 0 resistance?
- sanxiyn 3y agoSure, replacing copper wires help too, but the real deal is to replace copper interconnects inside the chips. It looks like the company is going for replacing copper interconnects in chips.
- sanxiyn 3y agoSince there will be impurity anyway, there is no difference whatsoever in practice between zero and very very low resistance. Quantum Energy Research Centre in fact describes its resistance to be "lower than 1/10^4 of copper", not zero, which is very practical minded. Since the company specifically developed thin film by vapor deposition method, I think we can be sure that computing is the intended application. Search for my other comments for details.
- maebert 3y agoA few practical things that we need superconductors for which currently require very expensive cooling: 1) MRIs — could be way cheaper, smaller and more ubiquitous with room temperature superconductors 2) Maglev trains — superconducters expel a magnetic fields that can make things "levitate" (called the Meissner effect). Maglev trains have minimal friction and are incredibly energy-efficient. 3) Quantum computing — most designs require cooled superconductors. Room-temperature superconductors are a requirement for future portable quantum computers, or quantum chips that sit side-by-side in conventional computers There's a ton more implications, just think about how everything from electric cars to smartphones was only possible due to modern batteries — that's the scale of technical innovations that could be built on this.
- raj33krish 3y agoThis is why space exploration is important. If we could find some astroid having superconductor materials at room temperature, everything will be revolutioned here.
- barabba 3y agoI strongly disagree with this view. We don’t even know if such material can exist, and the intersected odds of it 1) existing 2) naturally and 3) us stumbling into it in the short term are astronomically low. Not saying space exploration is not important, but the reason you cite for it is about at the bottom of the list.
- Affric 3y ago> Space exploration > Astronomically low Why, yes, my dear fellow. That’s the name of the game.
- s1artibartfast 3y agoWhat a silly thought. It is far easier to explore materials and test them on earth than hope to find novel compositions on asteroids
- supriyo-biswas 3y agoSince I know nothing when it comes to superconductors and material science, can anyone summarize the differences between the original paper and this one? (No ChatGPT responses please.)
- sanxiyn 3y agoAs far as I can tell lifthrasiir is correct here: https://news.ycombinator.com/item?id=36953052 https://news.ycombinator.com/item?id=36953052
- Leonelf 3y agoIs this abysmal quality of figures and charts normal? I'd imagine the devices used for measuring allow exports of CSVs and thereby enable external generation of proper figures instead of these pixely-screenshot-type pictures...
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- duringmath 3y agoAll this LK-99 related activity is exciting and all, too bad Twitter hype merchants hijacked the narrative (first Al now superconductivity they got them in every flavor it seems). It's important to remember that scientists are people too and they'll bandwagon trending claims to get their name out there. I'm no expert but the videos here are far from convincing and the other paper about simulating LK-99 is just that a simulation and parameters can be manipulated to induce almost any outcome.
- kijin 3y agoElon Musk must be feeling much better lately, having confirmed that Twitter is still relevant.
- fastball 3y agoAnd yet you'd think Elon Musk would've been quick the jump on this particular bandwagon – in past years I would've expected Musk to have setup competing teams at Tesla and SpaceX, first to replicate wins. Alas recently it seems that he does not have the singular focus he once had.
- fragmede 3y agoI am sure materials nerds (said affectionately, I am a computer nerd) at materials labs at top corporations, like SpaceX are working on this. Picture this. You're a material's person. You have a collection of each of the elements in the table of elements. You've got a successful career in your field. You've got your dream job working in a materials lab as a scientist or engineer. Along comes this paper, describing a pretty easy process, with things you already have on hand, to create a revolutionary new material that will change the world, if the paper is true. That person, at SpaceX, Apple, BASF, Google, GE, Samsung, DuPont, everywhere where there are passionate materials people in a lab who just want to believe, is going to do it over the weekend and after hours, just for the fun of it, nevermind Elon. They might not have the showmanship for a Twitter account with millions of followers but they have the lab and the materials and the drive to make it. Musk doesn't need to setup competing teams, and if he had, would he be forced to tell the general public about it?
- delegate 3y agoFirst question: what kind of weapons will people build using this ?
- Timon3 3y agoThe obvious one would be stronger railguns.
- dtx1 3y agoTheoretically, could/should we use these for signalling as well? Small strands of superconducting wire instead of fiberglass?
- LordHeini 3y agoSure it would work like copper wire minus the losses due to resistance. Probably it would not make much sense to replace glass fiber because problems like (thermal) noise and cross contamination by other signals would still exist.
- jboggan 3y agoPreprint by Griffin from Livermore Labs gives a theoretical explanation of LK-99's superconductivity and also explains why labs are having a hard time synthesizing it. There are two Pb sites in the crystal structure that Cu can substitute at, the lower energy one does nothing but it's the higher energy site that creates superconductivity. https://arxiv.org/pdf/2307.16892.pdf https://arxiv.org/pdf/2307.16892.pdf "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."
- peteradio 3y agoWhat does this mean for synthesis? You just have to try a ton of times and get lucky? Is there some way to influence site substitution?
- syrgian 3y agoI'm guessing the diamagnetic property will make it easy to separate the successful bits from the unsuccessful ones at scale.
- jmartin2683 3y agoEngineer thinking, right there
- appplication 3y agoI was a chemistry major, but didn’t take it up as a career so I won’t pretend to be an expert. There are a lot of tools in the chemist’s cookbook for dealing with exactly this sort of problem. It doesn’t mean it’s easy, but experienced chemists will understand how to approach solving this.
- neuah 3y agoIn this version, in figure 6a and b the new log scale of the IV curve looks quite linear and increasing in the range of 150 to 250 mA. I thought that it should be flat if it was a superconductor (no resistance). Can anyone explain how that behavior still supports it being a superconductor?
- willis936 3y agoBecause you're not measuring a pure superconductor sample. To be able to observe the cliff on the IV curve you need enough of the current path in between the electrodes to be superconducting, but certainly not all of it will be. This is true even in commercial superconductors, just with the ohmic losses pushed down even further.
- neuah 3y agoAh that makes sense. Thanks!
- nemo44x 3y agoInteresting see Asian scientists working together on this. Grinding it out over years - doing the work. Meanwhile in Europe and America they sit in their expensive “centers” and “institutes” and ask for hundreds of millions more for their experiments which have resulted in incremental at best results. And that some had the gaul to mock the Korean scientists and their poor grammar and amateur labs. And now the West will iterate on the breakthrough. The opposite of how it has been.
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- mattfrommars 3y agoMakes me wonder if ChatGPT can be leverage as a tool be used to come up with room temperate superconductor material which human haven't thought of before? ChatGPT is literally built on collective human knowledge and massive amount of data. If ChatGPT has the power to replace software developer, this should be childplays.
- KennyBlanken 3y agoOnly on HN could someone say "well if a statistical language model can 'replace' a software developer, then one of the holy grails of material science should be child's play." Because clearly being a software developer is more difficult than scientific research... This is everyone's daily reminder that ChatGPT is not deterministic, does not think, does not reason, etc. It is a statistical language model that has been fed everything from star trek to research papers. It will confidently tell you how many bears russia has launched into space: https://mindmatters.ai/2023/02/lets-take-the-i-out-of-ai/ https://mindmatters.ai/2023/02/lets-take-the-i-out-of-ai/
- ShannonLimiter 3y agoI'm not sure if ChatGPT can solve super conductivity, but the current version of ChatGPT can handle the bears in space question and the Monty Hall problem from the linked article. GPT-4 was released a month after that article published and its problem solving capabilities are much more sophisticated than GPT-3.5 (which ChatGPT first used.) It would be interesting to find some new examples to test it with since some people will claim the model didn't getter smarter – it only learned the answers to those questions. In my anecdotal experience, GPT-4 is much better at problem solving. --- how many bears russia has launched into space: "As of my knowledge cut-off date in September 2021, there is no publicly available information to indicate that Russia has ever launched bears into space. The idea of sending bears into space might sound intriguing or humorous, but it's important to note that space missions are highly complex and expensive endeavors that typically focus on scientific research and exploration. Animals like dogs, monkeys, and mice have been sent into space by various countries to study the effects of space travel on living organisms, but bears are not among the animals known to have been included in space missions." ### The table didn't fit in the car because it was too small. What was too small?: "The sentence is somewhat ambiguous, but the way it is constructed suggests that the car was too small to fit the table. The phrase "it was too small" refers to the car, and this is why the table didn't fit inside." ### There are three doors with a $10,000 hidden behind one door and a bag of goldfish hidden behind each of the other two doors. You choose Door 3. No matter which door you choose, the host will show you a bag of goldfish behind one of the doors you did not choose (say, Door 1) and then ask if you wish to switch your choice to the remaining door. What is the probability of winning the $10,000 prize if you do switch?: "The situation you're describing is known as the Monty Hall problem. It's a probability puzzle named after the host of the American television game show "Let's Make a Deal." The problem can be analyzed using conditional probability. Here's how you can think about the situation: 1. *Initially*: When you first choose a door (e.g., Door 3), there is a 1/3 chance that the $10,000 prize is behind that door, and a 2/3 chance that the prize is behind one of the other two doors (Door 1 or Door 2). 2. *Host's Reveal*: The host, who knows what's behind each door, then opens one of the other two doors to reveal a bag of goldfish. This does not change the initial probabilities. 3. *Switching Doors*: If you switch your choice, you'll win the $10,000 prize if and only if your initial choice was incorrect (i.e., you initially picked a door with a goldfish behind it). Since there was a 2/3 chance of that happening, there is a 2/3 chance that switching doors will lead you to the prize. So the probability of winning the $10,000 prize if you do switch is 2/3, or approximately 66.67%."
- RyanAdamas 3y agoFor all of the "what will this mean if true" posts; this is a foundational technology that will produce other technologies and advancements we can't yet determine. If it's able to enhance current quantum computer's efficiencies, power, and reliability, by a magnitude, that in and of itself would catapult new technology discoveries in other areas which would likely create a self-reinforcing feedback loop of advancement. It's not just about the trains or the chips, it's about the problem solving potential this material has by enhancing currently difficult to build and contain technologies. What if we discover that a room temperature superconductor in a ceramic form is necessary for telepathic communication via prefrontal cortex plates? Sci-fi, but the point is we can't really know what will come of it especially when we're talking about problem solving machines that go far beyond the human brains capacity for problem recognition.
- ChikkaChiChi 3y agoAre there any indications how scalable LK-99 production might be if proven out? Are we looking at exotic materials and processes or something that requires little tooling and common elements that will keep the cost low?