So the brief summary of where this whole #lk99 thing is now (keeping in mind that I am not an expert on this, I am just often good at absorbing and synthesizing information I'm interested in - I am trying my best to be skeptical and represent things clearly), without links because I'm tired but it's not too hard to find things at this point:
- one of the original papers was updated on arxiv with some errors fixed and some new graphs. Apparently mildly helpful but nothing very groundbreaking. It sounds like the process described in the paper is old - from their initial attempts to replicate what might have been a somewhat accidental discovery.
- there's also patents, and those have another description of process that is slightly contradictory but may also be old.
- Allegedly there's a paper going through "proper" peer review (not the kind that's happening on the internet right now but the very formal journal process) that might have their most up to date method. They've talked about helping reproduce after that goes through review.
- conflicting reports of the original lab giving samples to other labs for characterization. MIT might have one? Unclear.
- so many reproduction attempts going on that prices on precursors has spiked. Probably limiting the number of Western labs that can do it. Chinese labs seem to just have the stuff on hand so they have a head start and there are a lot of them.
- a theoretical physics paper showed a possible explanation for how it might be superconducting using simulation software came out, but there's a lot of caveats around how it applies to the real world. It does however imply that the thermodynamically preferred chemical reaction would produce a non-superconducting crystal though, so that might explain the difficulty producing pure samples of the "good kind". The produced material is likely mostly not special.
- the first round of replications to finish (other than the Russian lady I mentioned up thread) were negative, from an Indian lab and a Chinese lab. Neither reported either diamagnetism ("floating rock") or superconductivity.
- today a *bunch* of videos out of Chinese labs have shown samples floating over magnetic fields of both polarities (diamagnetism). The samples are very small and chunky. None of those have come with successful superconducting tests but, if I understand correctly, this is hard to test with these kinds of samples because the impurity of any sample large enough to visibly show diamagnetism would also act more like a semiconductor or even a resistor.
A lot of this seems to really hinge on the likelihood of a diamagnet that is this strong and not a superconductor. There are other non-superconducting diamagnets, but they are not this strong.
Also, it's likely that if it *is* superconducting, it's a new kind. Lots of talk of "1d superconducting" which I think means that it has a high degree of directionality vs other SCs. This means that it wouldn't do the "flux pinning" thing that others do because it will slide along the flux lines rather than getting stuck in a minima. But that is an extremely lay understanding of it so don't take my word for it.
To me this looks like a "where there's smoke there's fire" kind of thing. At this point, whatever it is, it seems to be at least novel and likely to open up new avenues of research. The videos by other labs showing similar magnetic effects make fraud seem unlikely, and might already by better replications than any of the early ones that happened with the cold fusion thing in the 80s. Certainly they're more visceral and less abstract.