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Wow, is this it? Is this the confirmation?


From what little I understand the levitation effect doesn’t necessarily equal all the properties of a superconductor. It’s one of them though.


Are other forms of diamagnetism temperature dependat?

Because this one is.


Yes, there exist diamagnetism-paramagnetism phase transitions.


I believe there’s no way to stably suspend an object on permanent magnetic fields, so if this is stable and doesn’t fall down then it’s hard to argue superconductivity isn’t involved.


There are diamagnetic non-superconductors like pyrolytic graphite that can also evade Earnshaw's theorem, but this would be the first metal with this strength of diamagnetism at room temperature AFAIK.


Pyrolitic graphite can evade Earnshaw's theorem only with either specific magnet array shapes or with rotation, they still can't stably levitate on a regular dipole without rotation.


It can be done at all with a static arrangement of magnetic fields, though? Ooh.


Isn’t that those floaty spinning desk toys are?


You mean the ones with a DeLorean or whatever? Those are powered closed-loop-control devices. Or the spinning tops (Levitron etc.?) Those are dynamic and fall down when they stop spinning.


Those usually use active electromagnets, which also bypass the preconditions of Earnshaw’s theorem.


You can stably suspend graphite pencil lead on permanent magnetic fields. E.G.: https://www.youtube.com/watch?v=yeIizmhzPQc


True, but only trapped within alternating N/S permanent magnetic poles... so it's possible to fool other people, but you won't be fooled yourself. Just don't use that magnetic setup. Superconducting materials will levitate in the field of a single magnetic pole.


On an array of magnets, but not on a single magnet.


Good point.


Not on a single magnet though, it has to be a shaped array.



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