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Comment by m3kw9 | Hacker News Reader

It didn’t pin, it bounces, if it was flux pinning it would not bounce when you push it down.

That's not true. Here's a video from a few years ago [showing a superconductor flux pinning](https://www.youtube.com/watch?v=OSojjjvRCR0). You can see from the video it's moving around. Also if it didn't move when you applied a force to it that would be quite the immovable object.

Another one that looks quite like the behavior shown here: https://www.youtube.com/watch?v=R2Hy6F_8n58

Flux pinning doesn’t mean it can withstand all forces it just means it will return to where it was

What about those Flux pinned maglev "trains" you see on YouTube?

What do you mean "what about?" them? Can you post a video of any of those that don't jiggle when poked?

The idea of those (i.e. like this https://www.youtube.com/watch?v=AWojYBhvfjM&vl=en) is that they're an example of equi-potential behavior.

The superconductor can move because it's staying at a consistent height.

The video linked is also pretty good at showing similar behaviors to the sample of LK99 we see claimed in the video: the superconductor can wobble, shake and does return to it's original position (or tries to) - but it's got a lot more mass.

And when you change the mass of the train the height of levitation changes.

Yeah, it's jumping back to a fixed position which isn't how I thought the Meissner effect worked. Since this seems to be posted by someone reputable though it's weird they missed that.

Flux pinning is distinct from the Meissner effect

NileRed at 32:30.

https://youtu.be/RS7gyZJg5nc

Not true. NileRed shows it at 32:30

https://youtu.be/RS7gyZJg5nc

That's how a levitating train levitates.

If no one has ever seen NileRed's video before, check out some of his popular videos on practical organic chemsitry.

Things like making hot sauce from latex gloves, or turning toilet paper into high proof alcohol.

He's a fantastic no-nonsense youtuber.

Ok my bad

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