A Levitron and Earnshaw’s theorem.

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Earnshaw's theorem, derived from Maxwell's equations, typically prohibits stable magnetic levitation in static configurations. However, the levitron serves as a counterexample, as it operates through dynamic motion rather than remaining static. The theorem does not apply to moving ferromagnets, which allows the levitron to achieve levitation by spinning. This motion creates a situation where the conditions of Earnshaw's theorem are circumvented. Thus, the levitron demonstrates that while Earnshaw's theorem generally restricts magnetic levitation, exceptions exist in dynamic systems.
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The Earnshaw’s theorem comes directly from Maxwell equation so it should be unavoidable in any classical situation. The theorem usually disallows magnetic levitation. However, there are loopholes. Quoting wikipedia "Earnshaw's theorem has no exceptions for non-moving permanent ferromagnets. However, Earnshaw's theorem does not necessarily apply to moving ferromagnets".

The usual counterexample to the impossibility of an equilibrium situation for magnetic levitation is given by the levitron
Open article on the subject: https://iopscience.iop.org/article/10.1088/1361-6404/abbc2c

I tried the literature on the topic, but I still can't understand what is actually happening with the levitron and the Earnshaw’s theorem. Is the theorem simply not applicable to the levitron? why? how?
 
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andresB said:
The Earnshaw’s theorem comes directly from Maxwell equation so it should be unavoidable in any classical situation. The theorem usually disallows magnetic levitation.
It disallows stable static configurations.
andresB said:
Is the theorem simply not applicable to the levitron? why?
Because it spins, so it's not static.
 
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