4 ms·
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 supercondu
by taneq 3y ago
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.
- stevespang 3y ago[dead]
- johncolanduoni 3y agoThere 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.
- sudosysgen 3y agoPyrolitic 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.
- taneq 3y agoIt can be done at all with a static arrangement of magnetic fields, though? Ooh.
- TylerE 3y agoIsn’t that those floaty spinning desk toys are?
- johncolanduoni 3y agoThose usually use active electromagnets, which also bypass the preconditions of Earnshaw’s theorem.
- taneq 3y agoYou 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.
- floxy 3y agohttps://en.wikipedia.org/wiki/Diamagnetism https://en.wikipedia.org/wiki/Diamagnetism https://en.wikipedia.org/wiki/Earnshaw%27s_theorem https://en.wikipedia.org/wiki/Earnshaw%27s_theorem
- jamesakirk 3y agoYou can stably suspend graphite pencil lead on permanent magnetic fields. E.G.: https://www.youtube.com/watch?v=yeIizmhzPQc https://www.youtube.com/watch?v=yeIizmhzPQc
- montecarl 3y agoOn an array of magnets, but not on a single magnet.
- jamesakirk 3y agoGood point.
- po 3y agoTrue, 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.
- kadoban 3y agoNot on a single magnet though, it has to be a shaped array.
- deleted 3y ago[deleted]