Flux Pinning in sample of LK-99?

[semajian]

It's hard to imagine how this could be faked short of digital manipulation, and it seems implausible that it would be a known high TC superconductor because it would warm up too fast. Absent the former explantation, I'm starting to believe this is real. Also, it's not like all the author's are unknown hacks. Hyun Tak Kim has about 10k citations (Google scholar, which sometimes combines people who have the same name though) and authored a paper in scientific reports which got L&K interested in collaborating with him. The guy seems to know superconductivity so I'm feeling rather optimistic about this.

[thecopy]

According to this video: https://twitter.com/xmal/status/1300754522218913799 it is possible to have stable levitation using a copper plate below the magnet.

OP's video has two stacked metal objects – could the lower one possibly contain copper?

[stavros]

> It's hard to imagine how this could be faked short of digital manipulation

So, it's easy to imagine how this could be faked.

[Qem]

> Hyun Tak Kim has about 10k citations (Google scholar, which sometimes combines people who have the same name though) and authored a paper in scientific reports which got L&K interested in collaborating with him.

It appears he was a latecomer to the project, mostly borrowing his reputation to the trio of anonymous, non anglosphere native original authors.

[totetsu]

The flake is a magnet, and a known type two liquid nitrogen cooled superconductor is inside the blocks at the bottom?

[pera]

Seriously? To me this looks like a chip of graphite glued to an invisible thread. The way the object moves is not what I would expect from magnetism (see second 10 for instance)

[lucubratory]

1. This video is originally from an anonymous Douyin account. There is no verification that it is associated with a real replication attempt, from traditional academia or citizen science. There is a previous video on the channel showing the partial levitation more common to LK-99, but it likewise has no particular evidence it's not just a flake of pyrolitic graphite. It is claimed to be associated with a specific person but no evidence is provided. There is no reputation to be lost if this is a fake.

2. In the video, while the effect dynamics look quite good for flux pinning, there is some really concerning artifacting on the alleged LK-99 piece while it bounces. Specifically, it looks like it may be attached to a taut horizontal string that has then been edited out, but they didn't successfully rotoscope over the parts very close to the alleged LK-99 piece during specific moments. This could just be a compression artifact, I have never seen one like this but apparently this is a capture of a capture by the time we can access it, and I don't use Douyin or Bilibili so I wouldn't have a lot of familiarity with what their compression artifacts look like.

Basically, I am pretty sceptical about this video in specific. I do think LK-99 is more likely than not at this point, but I also think it's more likely than not that this specific video is not real.

I also think it's extremely likely that as LK-99's profile raises and VFX editors get more familiar with what exactly a real video should look like, convincing fakes are going to be produced and go viral. The most common way this happens is that the VFX artist does it as an exercise and shows a few people without ill intent, but the video is then reposted by other people a few times until it reaches a wide audience who has no chance of knowing its origin. However, there are some scammers/influencers who are good with VFX and can fake a video themselves.

Basically, be a little bit careful about video, and things you should want are: the camera is moving around the piece and not static, the light changes during the video, the pieces themselves are moving, you see the pieces getting set up or finished later, and there's stuff moving all around the object to make strings less likely.

[delabay]

All great reasoning. Unfortunately I believe it's a fake from an Occam's razor standpoint: it's too short and precisely framed.

It's trivial to record a video 20x longer with a moving POV without revealing IP or secrets, but far from easy to product 20x more doctored vfx.

[cpleppert]

I looked at the highest quality and the artifacting is just crazy here. There are no artifacts around the instrument at all, just on the supposedly levitating rock. The quality on this and the other video from the user looks like its very good so I don't really buy this.

The context here is rather strange as well, the same user uploaded another video that no one would believe actually demonstrated the meissner effect. Its a very small magnet on just a piece of paper. Did the user try again with this video?

[irthomasthomas]

Yeah, why on earth would you use only a wide angle lense to film something microscopic? You would zoom in close to your amazing discovery. But, this way, the interesting thing is a only a few pixels, and can easily be computer generated. Every video I've seen has some logical flaw like that.

[klysm]

Those tiny “artifacts” look like they’re smaller fragments of particle stuck to the big one to me

[kzrdude]

Nitter: https://nitter.net/Andercot/status/1687740396691185664

[kzrdude]

Alternative video link here, but it's in chinese so no idea if it gives any more information about the source: https://news.ycombinator.com/item?id=37010498

[Kiro]

OT but why do I need to press "enable this playback" and reload the page to view the clip? What does it do?

[arecurrence]

In the lk99 subreddit, a higher res video was posted https://www.douyin.com/video/7263715495256378659

[phreeza]

Someone linked to this on the manifold market: https://imgur.io/a/AY1oaIO it does look a bit weird to me but I am not expert enough to tell if this could be explained by optical/compression effects.

[incrudible]

Looks unlike any compression artifact I have ever seen. Two remarkable discoveries in one video! Big, if true.

[shawabawa3]

This is basically proof of room temperature superconductivity correct? (Of course assuming it isn't a hoax)

[dmitrybrant]

Assuming everything in the video is real, the only remaining question is: what is the actual temperature of that sample?

If all of this checks out, then it's a new era.

[oxfordmale]

No, it is not yet proof of superconductivity. It also requires measurements of the electric resistance as function of the temperature.

For now LK-99 is an material that displays some of the superconducting properties at room temperature.

[kzrdude]

Let's use the word evidence and not proof for each part of the puzzle

[blablabla123]

I mean based on current understanding a previous video that showed levitation independent of the orientation was already sufficient to show it's not diamagnetic but superconducting. Assuming this is not a hoax actually the very first video together with the paper already shows everything. (Levitation, mentioning of zero resistivity regions)

Although generally the accepted method is that other labs reproduce it and that the paper passes peer review. Some videos aren't enough.

[pera]

This is an hoax and it's sad to see people like Sabine Hossenfelder falling for it so easily:

- video recorder in a kitchen or living room

- created by some random tiktok account

- no credentials, no description

- tagged "mysterious"

It's hard to understand how anyone would believe this, specially after so many other fakes

[BasedAnon]

is it possible in theory that flux-pinning could occur without actually causing superconductivity? because LK-99 seems to be decoupling alot of properties we thought were coupled if I'm understanding correctly?

[traverseda]

It could be an entirely new hitherto unobserved phenomena, but that seems pretty unlikely. I think that having a bunch of tiny superconductors chunks separated by a regular conductor would explain a lot.

[jacquesm]

That would require 'new physics'. I think most of the weirdness stems from either (1) sample impurity, (2) an extreme form of that where the active bits are really tiny in a large chunk of inert stuff or stuff with its own electromagnetic properties or (3) being mistaken about it being a superconductor in the first place.

[justicz]

The post just says the video came from BiliBili. Does anyone know the actual source? I want to believe but this video is suspicious.

[fghorow]

An oddball question for the device physicists here:

Assume for now (subject to verification, of course!) that this material is a non-Cooper-pair superconductor.

Could one still build Josephson junctions -- and SQUIDs -- from this material?

If the answer is "yes", it's going to make a whole lot of magnetotelluric geophysicists very, VERY happy.

[eugene3306]

Is this material safe to handle?

It feels like this thing soon will start appearing all over ebay and aliexpress

[foobarian]

I hope it is. It will be a perfect toy for little kids, right along the little ball magnets.

[makeworld]

It has lead in it.

[naillo]

Would that be legal, considering they have a patent (pending) for it? Not denying it won't appear anyway just curious

[PUSH_AX]

Forgive me, I know little about these things, but what’s the relationship between this phenomenon and the quantum locking seen in other super conducting magnets, this looks as described as “pinned”, what would allow it to behave like the famous video of the magnets levitating around that circular track: https://youtu.be/Ws6AAhTw7RA

[im3w1l]

It's possible that I misunderstand, but I think the title is a little inaccurate. Flux pinning goes beyond just levitation. In the embedded video we can see that the sample is not just levitating freely above the magnet, but it levitates above a certain fixed point. After gently poking the sample we can see it returning to its original position and orientation.

[amelius]

Can anyone explain if the specimen was found through rigorous research or just sheer luck?

Because it is starting to seem like it's the latter.

[gonehome]

No idea if accurate but there was this which is interesting: https://news.ycombinator.com/item?id=36996337

> “ Specifically they were one of the last believers of long-forgotten Russian theory of superconductivity, pioneered by Nikolay Bogolyubov. The accepted theory is entirely based on Cooper pairs, but this theory suggests that a sufficient constraint on electrons may allow superconductivity without actual Cooper pairs. This requires carefully positioned point defects in the crystalline structure, which contemporary scientists consider unlikely and such mode of SC was never formally categorized unlike type-I and type-II SC. Professor Tong-seek Chair (최동식) represented a regret about this status quo (in 90s, but still applies today) that this theory was largely forgotten without the proper assessment after the fall of USSR. It was also a very interesting twist that Iris Alexandria, "that Russian catgirl chemist", had an advisor who was a physicist-cum-biochemist studied this theory and as a result were so familiar with the theory that they were able to tell if replications follow the theoretical prediction.”

So it might be an old hypothesis brought back?

[sidlls]

A very large quantity of discoveries in science are a combination of "well, that's odd" and the "sheer luck" associated with the circumstances producing that statement.

(This isn't a commentary on the truthfulness of the superconductor claims.)

[scarmig]

There is a combinatorial number of different materials out there. They chose a particular small subset of them that they predicted might have some interesting properties and, over two decades, discovered one that may have those properties.

Most hypotheses are wrong, and even if they turn out right it may well be a case of being right for the wrong reasons. Regardless, this is top tier research: unglamorous, uninstagramable drudgery guided by intellect. Sure, there's luck involved, but research always involves luck.

[rowanG077]

This is a very odd question to me. All research is essentially this may or may not work. That's why you test it. In a sense finding something cool is a very large part luck.

[kijin]

Does it matter? Even "rigorous" research depends on luck in many cases, because there are so many unknowns. Theory helps reduce the search space, but there are situations when a brute-force attack is the most efficient way to answer the all-important question: is this real?

[mytailorisrich]

Many things were discovered out of luck in the course of research.

[mcpackieh]

Trying lots of stuff for years and years until something works, aka rigorous research and sheer luck.

[skecpical222]

The sample most probably sticks to a flexible membrane above the magnet (to something like a transparent contact lens - one can even clearly recognize a round circumference on the magnet plate surrounding the green junk).

[amai]

So lk-99 is supposed to behave like a type-II superconductor? Is this expected for a room temperature superconductor?

[incrudible]

The most likely explanation: This is a speck of dirt on a string filmed as an attempt to manipulate the prediction markets.

[kimorpark]

Elsa zhou says the wust student denied he posted it so authenticity cannot be confirmed. Assume fake video 4 now