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Ferromagnetic half levitation of LK-99-like synthetic samples

arxiv.org

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Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#121

Earlier quoted context omitted.

There 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…

Doesn't diamagnetic levitation require a specific arrangement of the permamagnets that is not recreated in these videos?

That's not clear, but either way--as I've told you several times--there has been no credible demonstration of stationary levitation for even very weak uses of the word "credible."

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#122
Since someone blamed "Soviet fan fiction" in which I did take a part (oops) [1], let's make my opinions explicit. I'm very sure at the moment:

- That the publish of two arXiv papers was accidental and the second paper was only published to claim the proper authorship, thus the exact publish date was never controllable.

- That top-tier Chinese universities do use Bilibili to post early results. This makes very hard to dismiss all Bilibili videos, though probably most would be.

- That you can produce something like the floating rock as seen in the original videos with a synthesis method similar to the paper states.

- That the synthesis method has an extreme variability depending on parameters. No single reproduced LK-99 samples are same.

- Thus, that Q-Center did make something according to this synthesis method as well, but that is probably different to other reproduced samples.

I'm cautiously positive that:

- That LK-99 is not a deliberate fraud. The most probable possibility at the moment is therefore an honest but misguided mistake. I still reserve a nonzero but not large probability (5%) that this is indeed novel to superconductivity.

- That LK-99 indeed has some peculiar properties when synthesis parameters are controlled right. The large variability does suggest singularities in the middle and Q-Center might somehow have gotten the jackpot.

- That at least some authors (notably Hyun-Tak Kim) are clearly distinguishing the superconductivity and superconductor [2]. In the other words, they are aware that LK-99 (supposedly) exhibits superconductivity but might not be considered as a superconductor.

- That there is a Russian group of scientists that claim some relevant knowledge and feel uneasy about the apparent dismissal of it. This might be the most controversial point I like to make, and my relative confidence partly comes from private information (like, I have verified the credential of Iris privately) so you don't have to completely trust me on this.

- That the research group has not settled on a single theoretical explanation. This is probably why all LK-99 papers were different from each other in theory, and also why Young-Wan Kwon became "disgruntled" as Hyun-Tak Kim might have been his substitute.

- That the late professor Tong-Seek Chair is indeed a madman, regardless of the veracity of his theory.

I have suspicions that:

- That the paper is intentionally vague about the synthesis method. This method is notably different from what their international patent describes, and this is AFAIK typical in the material science. Probably the paper describes a low-yield and low-quality but easy method, and their trade secret is an efficient process.

- That Russian scientists and possibly LK-99 folks do have some theory that describes LK-99 better. I had to slightly weaken this point in the previous article because the actual difference was very unclear to me and other proofreaders (we have discovered this during the rewrite to avoid apparent misreadings). I now suspect that there is no actual theoretical difference but different paradigms may have resulted in different blindspots. So the "acceptance" of theory without paradigm may be seen as the fake acceptance to them, possibly explaining their sentiments.

- That China realized this possibility as well and wanted to maximize their leverage, explaining why China universities go crazy about this.

- Therefore, under these assumptions, that Q-Center's apparently suspicious behavior can be fully explained.

I believe all of them needed me no advanced physics knowledge to derive. Any questions about those points are welcomed.

[1] See the original reply https://news.ycombinator.com/item?id=36996337 and the current version https://hackmd.io/@lifthrasiir/lk-99-prehistory for the context.

[2] https://hackmd.io/@sanxiyn/seize-interview

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#123
post #77

Earlier quoted context omitted.

There are at least 2 samples definitely produced: one in the original videos and another in the video released by Hyun-Tak Kim via nytimes which definitely look different. It is unclear if the sample sent to KENTECH for the analysis is the first sample or a fresh one. Young-Wan Kwon is also known to have his own sample (confirmed in MML 2023 sightings), but it is unclear whether it's distinct from other samples too.…

If you cite Korean (or Chinese or Japanese) names, please write them correct. There is no Hyun-Tak Kim, he is called Kim Hyun-Tak. Likewise Kwon Young-Wan. In Korean it's trivial to detect, in Chinese not so, in Japanese very hard.

Ouch. This comment backfired quite badly. Turns out the person being replied to is Korean, the commenter is likely not, and in addition this is how the authors wrote their names themselves.

Yet I do not wish this comment to be snarky. I’m interested in the broader perspective (and I apologize in advance to the parent for using this as an hook). The comment seems common of the present era in which polarization (leading to prejudice against anyone we believe is outside our in-group), and short attention span (leading to drive by/poorly researched comments), combine to low empathy among us. And just to be clear, I’m not putting myself above this, on a bad day this kind of comment could have come from me.

Am I right and things were better on the past on the empathy axis? Or am I exaggerating and getting old?

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#124

Earlier quoted context omitted.

> Ferromagnetic explains half levitation but it doesn't explain full levitation No one reputable has actually demonstrated full levitation, including the original team. > Sure, metal ones are, but Are ceramic ferromagnets (without iron) common? That lone electron in an orbital is pretty important. They literally reproduced this behavior with a substance that looks identical to the original LK-99, so while it would be…

Never claimed it was impossible, just that it's rare. > No one reputable I don't care about reputability of anyone unless they have a known past of fraud. Gatekeeping in science is lame unless someone makes a claim to break well understood theory or claims to do something technically difficult. RTSC is neither. Do you think this video is faked?: https://twitter.com/Andercot/status/1687740396691185664?s=20

The Chinese originator of that video has since admitted it's fake.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#125

Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?

A magnetic levitation demo indicates a possible Meissner effect (which is refuted here by this paper), and this is so much easier than a resistance measurement, which is a delicate task and susceptible to experimental errors. So levitation is used as a quick "first check", especially when you don't have a full lab setup to do other tests, which are much more complicated (in addition to a levitation test or a resistan…

> One cannot measure superconductivity with an ordinary ohmmeter.

But one can measure electrical resistivity, and if the material's resistivity is much lower than that of ordinary materials, that would be super interesting and valuable, regardless of whether it is a "true" superconductor or not.

If this relatively cheap material had a resistivity around 1/100th that of copper, that would be an engineering breakthrough, and determining that doesn't seem to require a super complicated lab setup.

Do we have an upper bound on LK-99's resistivity, and is that upper bound substantially lower than the resistivity of typical conductors?

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#127
post #103

Earlier quoted context omitted.

This question has been asked with near identical or very similar wording in almost every LK-99 submission I've seen over the last week or so... Is there something botnet-y happening? I find it hard to believe anyone reading similar threads could have missed the numerous answers to this and similarly-formed questions that have been offered lately.

At least nobody has asked about the real-world technology implications in this thread yet.

now I have to get out my bingo card and ctrl+f "hoverboard" and "maybe purity",

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#128
post #103

Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?

This question has been asked with near identical or very similar wording in almost every LK-99 submission I've seen over the last week or so... Is there something botnet-y happening? I find it hard to believe anyone reading similar threads could have missed the numerous answers to this and similarly-formed questions that have been offered lately.

Yes, and it is getting a little annoying at this point to be frank.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#129

Earlier quoted context omitted.

How 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.

> 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.

I think this is functionally equivalent to the status quo?

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#130

I knew it was fake, there would have been a huge rise in the stock market. Financial markets would have sniffed this out. The market never lies. If anything, this was an obvious opportunity to short it on prediction markets.

The market isn't magic, it too would only rise with sufficient repeatable confirmation and indications of viability for mass production and application. After all, we do have knowledge of 'magic' materials like carbon nanotubes and graphene, and yet the stock market hasn't gone crazy over them.

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