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by WJW 1048 days ago
Magnetic levitation can't be done with normal magnets alone: https://en.wikipedia.org/wiki/Earnshaw%27s_theorem

TL;DR: Normal magnets have two poles, and will try to flip themselves around to achieve a lower energy state. You cannot levitate a normal magnet on another magnet without mechanical stabilization. Superconducting materials actively repel all magnetic field lines and can achieve levitation without external stabilization.

3 comments

> “You cannot levitate a normal magnet on another magnet without mechanical stabilization”

The mechanical stabilisation is right there in plain sight where one side of the magnet is clearly resting on the other magnet (physically in contact). Anyone who’s played around with magnets that are heavy and too weak to flip themselves around will not be satisfied with this video. It could be explained by two South Poles opposing each other.

> Magnetic levitation can't be done with normal magnets alone

Technically it can be done with an array of magnets with opposing polarities.

Without more details from on this video's source and legitimacy, one could argue that an array of magnets is hiding under the 'single magnet' cover plate.

I am not saying this is a hoax, but as exciting as this seems we just have to wait it out for more replication publications to make that call.

If we doubt the legitimacy of basic claims like a fair setup of magnets, then there are much easier ways to create a fake, like just tie something on top of it.. but why would we doubt the legitimacy of reliable institutions?
Grand parent was saying it's "impossible". I say it is _technically_ possible.

To which I added:

"I am not saying this is a hoax, but as exciting as this seems we just have to wait it out for more replication publications to make that call"

It has been a little over 2 weeks since the first pre-print from Korea University.

The hashing out of a fabrication process with less impurities will be a long process. My point is not that everyone is pulling a con, my point is that we need to wait it out.

> Technically it can be done with an array of magnets with opposing polarities

How?

An example of Pyrolytic Carbon levitating on top of a 2x2 matrix of magnets. [0]

[0] https://en.wikipedia.org/wiki/Diamagnetism#/media/File:Diama...

No, it mathematically cannot be done with any combination of permanent magnets.
aside from non-superconducting diamagnetic materials, I think it can be done with non-static magnets, for example: https://en.wikipedia.org/wiki/Spin-stabilized_magnetic_levit...
Oh of course. Brainfarted and fused "static permanent magnets" into just "permanent magnets".
Why can't the weakly positive results be explained by an irregular formation of magnetic crystals that stabilizes the forces, in a way a single magnetic object cannot? As in, not a superconductor, just a novel configuration of magnetic particles?