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XorNot

That video isn't very convincing. The usual test is that the material can float above the magnet.

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This is the better video:

https://sciencecast.org/casts/suc384jly50n

That looks like a chunk of pyrolytic carbon, which can also float above a magnet.

AFAIK doesn't pyrolytic carbon need a N-S field in order to levitate? That's the one key difference I can see - this looks like the traditional superconductor trick of just levitating in a simple field.

i.e. not like some of the ones you'd see here: https://www.youtube.com/watch?v=Vy9uWXgbKy0

Not if a corner is anchored, as is visible in their video. This is an obvious scam.

This video seems to show the best example of a possible effect like that: https://www.youtube.com/watch?v=VC3r9-OaWes

But it still looks dependent on their being a NS pole at a corner.

That said...from this video https://sciencecast.org/casts/suc384jly50n I'm very suspicious of the behavior you see in the last few seconds where it gets pushed over to the corner and seems to fall right to the magnet That would be consistent with their being a ring magnet underneath the top magnet their, and once suitably over into the corner it loses the diamagnetic property because there's no N-S pole. The "seam" on what should be a bulk magnet in both videos that are out seems like an obvious problem.

So yeah...I think put me down for this is diamagnetism with pyrolytic carbon (the image in the paper also notably hides what you see in the video - that there's a seam on the magnet where it looks like it's a stack of two).

Yes, this is either a fraud or the real deal. Not an honest mistake or pushing the boundaries of data fitting (a la, phosphine on Venus, etc.).

The effect is weak, but seeing that it behaves the same by flipping the magnet means that it can't be a standard magnet like we're used to seeing. (If I understood some of the other comments correctly).

Other comments. https://news.ycombinator.com/item?id=36867758

Copper does this already. It's not like ferromagnets. https://www.youtube.com/watch?v=sENgdSF8ppA

In the video, it's when they stop moving the magnet, it maintains its position, neither repelling nor attracting.

Several physicists have spoken up and said this, and a few other tells distinguishes it from any conventional materials, which is why they made the video to begin with I'm sure.

That said I'm just parroting back the things I've picked up from this discussion.

Unmoving copper also neither repels or attracts a magnet. Eddy currents impede movement of non ferrous metals in a static magnetic field. This looks like slow motion falling or resistance to spinning when the metal is in a fixed field. This is how auto belays work.

If you move the magnet, the metal will also move since you're inducing a current and the fields from the eddy currents will react against the moving magnet.

> This is how auto belays work.

That is super cool!

That said, I'm enough of a layman not to be able to connect this explanation to what I saw in the video.

Are you saying because it wasn't moving in "slow motion," we can rule out non-ferrous metals? Or are you saying the alternating movement/stillness of the magnet shows this?

When does the hanging copper maintain a position in the video? https://www.youtube.com/watch?v=EtVjGWpbE7k

All I see is the normal dampening and dragging effects that I show in my physics classroom.

As I've said, I'm fuzzy on the details, so I'm relying on the expertise of the physicists here.

I can tell it doesn't react to a magnet in ways that I'm familiar with (copper, iron, other magnets), but that's all the detail I can tell from the video.

Well after seeing the second video I'm pretty convinced it's superconductive or a good scam. The effect was probably just not strong enough in the first video.

I'm suspicious of the magnet. Take a real close look in the second video: the paper cuts the image so the seam of the magnet blends with the table. But in the video it looks much more obviously like there's two magnets stacked on top of each other.

Which is a weird thing to do when for superconductors you shouldn't need it, but for pyrolytic graphite levitation you would (to get an N-S pole).

It's also suspicious that there's not a control sample of copper in the video. Any scientist trying to be thorough would have controlled for this - shown that you don't get the same effect with just a copper sample as you do with a copper sample that's been coated.

If this enables monopole magnets?

That's one tell. There are several tells that, in combination, mark it as a super conductor.

But I'm just parroting back what the physicists in the thread have shared, so I might have some details wrong.

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