5 ms·
After reading the r/physics thread on LK-99 [1] I've cooled significantly on the matter. Basically: people who work in SC think the initial science seems very
by VHRanger 3y ago
After reading the r/physics thread on LK-99 [1] I've cooled significantly on the matter.
Basically: people who work in SC think the initial science seems very sloppy and the replication attempts don't come close to what you need to demonstrate a RT SC
[1] https://www.reddit.com/r/Physics/comments/15i3h9d/lk99_megathread/jus73e6/ https://www.reddit.com/r/Physics/comments/15i3h9d/lk99_megat...
- carabiner 3y agoPeople were saying the initial papers were trash in the first day of their release over a week ago, so that's ancient history and immaterial now. Same with the "replications," they're obviously insufficient when they're generating pieces the size of a pin head that can't be attached to probes. All of us are in a holding pattern waiting for some big lab like Argonne to confirm or deny its SC status.
- VHRanger 3y agoHow would you *deny* the SC status? Replications keep failing until everyone is pretty sure it's not it. Proving the absence of something is rare to see.
- dralley 3y agoChecking the original samples, for one.
- jacquesm 3y agoI hope that ultimately it will come to that because I don't think anything else will put this to rest one way or the other (unless it is 100% confirmed/reproduced by another lab). It also seems to be the shortest path to a resolution.
- willis936 3y agoThat also adds little value. It would add no information on whether or not the sample is a fluke. We need to understand the material properties and its composition.
- jacquesm 3y agoIf it is a fluke or not doesn't matter. The only thing that matters is whether or not it is real, not how it was made. If it is real then we can expend a fortune on the 'how it was made' question, if it isn't real we can all descend from this holding pattern.
- willis936 3y agoWhat benefit does that bring?
- fastball 3y agoAppropriate allocation of resources is intrinsically beneficial.
- willis936 3y agoExactly right. If we concede that our present level of societal R&D is appropriate then it's easy to argue that resources are presently wasted pursuing less promising leads.
- woeirua 3y agoUntil we have definitive evidence that LK99 is a SC, there's no reason to believe that it is a promising lead.
- gus_massa 3y agoIf it's real, "we" can brute force a reproduction. Just make each graduate student that works in a superconductivity lab spend two random months trying variants of LK99. The attempts will fail. The idea is that the rest of the time the graduate student will be making standard superconductor to collect enough boring papers to escape the rat lab. But if the LK99 clone is a lucky one, everyone in the lab gets a groundbreaking paper.
- jefftk 3y agoCouldn't there be solid evidence that the observed behavior was due to a different effect?
- deleted 3y ago[deleted]
- Jweb_Guru 3y agoThere is, a combination of strong (but not amazingly strong) diamagnetism at low field strengths and soft ferromagnetism (in floating samples) at high field strengths. Which is exactly what the paper in the link observed while getting the same results everyone else has. The only unambiguous sign of superconductivity was the original resistance graph which can apparently be explained by contact issues with four point probes (you can argue that they must have done many experiments and surely didn't cherrypick just the one where they found "superconductivity", but consider the quality of the rest of the paper...)
- throwawaymaths 3y agoDoesn't diamagnetic levitation require a specific arrangement of the permamagnets that is not recreated in these videos?
- readyplayernull 3y agoMaybe the original LK-99 sample was contaminated with actual high temperature superconducting impurities.
- worrycue 3y ago> How would you deny the SC status? Maybe we should adopt the stance that it’s not a SC by default and have the people asserting that it is prove that it’s a SC.
- colordrops 3y agoOr even better adopt no stance on truth value and rather adopt a stance on whether there is sufficient evidence to expend further effort. No need to guess at the truth. Just remain agnostic until you know the truth.
- jacquesm 3y agoExactly. That's the only reasonable stance. Everything else is just jumping to conclusions, positive or negative.
- worrycue 3y agoSometimes a decision has to be made though - e.g. is a particular person a murderer. In most countries, the burden of proof is on the accuser and the accused doesn’t need to proven his or her innocence and is treated as innocent until proven otherwise.
- jacquesm 3y agoSure, but science isn't a murder trial, it is entirely evidence based. Show the evidence, if there is none we'll move on and if there is you get a Nobel (in the case of superconductivity at room temperature and ambient pressure). We (the rest of the world) can't prove a negative, so it is up to the claimant to supply the proof. Given proof it will be believed, no proof then it's a no-op. With the murder trial you can assume a-priori that there is a murderer, the question then is 'who', not if a murder is possible or not. These are entirely different problems for a logic perspective.
- whimsicalism 3y agoI think this is functionally equivalent to the status quo?
- phyzome 3y agoWhat you'd have to do is 1) create bulk LK-99, 2) prove that that's what you'd created, 3) possibly also show that it's monocrystalline or something, and then 4) show that there's electrical resistance. The problem is that the stuff is really quite difficult to synthesize reliably. Until that can happen, good luck finding out in either direction!
- evanb 3y agoCool it down until you DO see a SC transition far below room temperature.
- protastus 3y agoThe SNR of this saga is very low. A speck of something floating under a magnetic field on a blurry video is not proof of room temperature superconductivity. We've seen memes, jokes, shitposting, bravado, Soviet fan fiction, play-by-play updates from non-SMEs cooking stuff under improvised conditions. No actual resistance measurement of LK-99 with a 4 point probe. If this is real, then discoverers found this in 1999, apparently couldn't synthesize with good yield, couldn't analyze rigorously, sat on the discovery for 24 years, were recently rushed to publish half-baked papers, and are now silent. None of this inspires confidence. LK-99 could hypothetically be the real deal, and I want to believe, but I'm patiently waiting for people who actually know what they're doing to offer experimental evidence.
- haldujai 3y agoAdding on to that: the researchers are from a private corporation that falsely claimed partnerships with several South Korean enterprises and universities which have all disavowed any connection, the "Quantum Energy Research Centre" website has gone private[edit: not suspicious as described in comments below] and the co-authors are apparently feuding over project direction with one of them since removed from the paper. I know nothing about the subject matter but as a curious layperson I've been surprised a pre-print is being taken so seriously with this background and have assumed people much smarter than me interpret the physics as plausible.
- lifthrasiir 3y ago> the "Quantum Energy Research Centre" website has gone private In this particular case however, the website repeatedly hit the daily traffic quota before the closure. So I guess it would be no surprise that the hosting provider [1] forced them to close the website. [1] The website itself was probably hosted by https://imweb.me/ https://imweb.me/ (the parking page also supports this observation---the asset path and the admin page path matches).
- haldujai 3y agoInteresting, so that's the expected parking page for such a situation? I have no idea how web hosting works in SK and was going off this article, my interpretation was that this was changed after the traffic warning hence why I assumed malice: While the company’s website previously displayed a message that it has been blocked due to excessive traffic, it has now been shut down altogether as of Thursday with a message saying that it is “under construction." I guess that's one less red flag. https://koreajoongangdaily.joins.com/2023/08/03/business/tech/Korea-Quantum-Energy-Research-Centre-superconductor/20230803184638075.html https://koreajoongangdaily.joins.com/2023/08/03/business/tec... Edit: Is the Safari translation of https://imweb.me/price https://imweb.me/price correct in saying unlimited traffic is 24,000 won ($18 USD) per month? If so, I'll add back that a private company that has discovered a room-temperature superconductor but is skimping out on $18/mo for web hosting does not inspire confidence.
- NovaDudely 3y agoI have been very cautious on any analysis on LK99 - especially my own. I have mentioned to many people that any potential application of this stuff comes with an 'if it is real'. That IF is doing a lot of heavy lifting and it has to be emphasized. I want this to be a thing, but it doesn't matter how much you want something to be true, it actually HAS to be true. A beautiful elegant idea can be crushed by a single ugly dirty truth.
- dylan604 3y ago[flagged]
- Teever 3y agoI would prefer if †his conversation wasn't derailed into one about politics.
- dylan604 3y agowasn't trying to go political, but used it as an example of the evidence not fitting your theory. so it's still some what scientific.
- InitialLastName 3y agoThere's a concept (presented as a contrast to "objective truth" and "subjective truth") called "intersubjective truth", which refers to ideas that are true because (and only to the extent that) a quorum of people believe they are true. Money, contracts and laws are all only words on a piece of paper in objective value. I can generate all of them myself, but unless other people start to treat them as if they are real they'll have all the power of words on paper. On the other hand, if a system arises where people believe those things are true and have value it can be used to build extraordinary things. Political systems are full of intersubjectivity (they mostly boil down to "groups of people coordinating societal resources, with the consent of enough of the governed"), so of course politics is an arena where "enough people believe this thing" is sufficient to generate truth.
- Accujack 3y agoYet somehow those "SC people" issue this opinion without having seen the final paper nor the lab data on the original sample, which is presently being examined as part of the peer review process in SK?
- gus_massa 3y agoThe final paper doesn't mater. If you are in the area, you can skim the paper and look at a few key graphics and tables. Those key graphics and tables should be in the initial draft, because the rest of the article is build around them. Perhaps the final graphs will be prettier, or they will fix some minor errors (like a missing label). (Sometimes it's more complicated. The initial and final version have bigger changes because the writer realize it's better to select other examples instead of the initial ones. But in this case I guess they don't have too many examples to cherry pick.)
- Accujack 3y agoIn this case, we have only a rough idea how close the leaked papers are to the final paper, with only one statement from a scientist at the national lab in SK stating that there are additional manufacturing steps in the final version of the paper. I suspect there's a large difference between what was leaked and what will be formally published.
- nntwozz 3y agoI cooled significantly after watching Asianometry on the history of superconductors: https://youtu.be/wUczYHyOhLM https://youtu.be/wUczYHyOhLM The research field is apparently fraught with failures when looking back at previous breakthroughs.
- kzrdude 3y agoNow, I don't have this guys credentials, but it sounds very close to "This is not a superconductor as we know them to be". Which almost goes without saying, because if this is a room temperature superconductor in some sense, maybe something quite different is needed to explain it. I think we should be excited for new physics.
- whimsicalism 3y agoNo, not at all. Meissner effect is constitutive of SC
- killerstorm 3y ago> Type-II superconductors do not exhibit a complete Meissner effect. Are type II superconductors not superconductors to you?
- whimsicalism 3y agomeissner effect != complete meissner effect, but i can see how that would be confusing there was no meissner effect measured in this substance