My favorite loophole for Earnshaw's theorem is spin-stabilized levitation. It has such an interesting back-story. A 'crackpot' tinkerer invented it, despite phy

My favorite loophole for Earnshaw's theorem is spin-stabilized levitation. It has such an interesting back-story. A 'crackpot' tinkerer invented it, despite physicists telling him it was impossible. It's an impressive accomplishment because the set-up is also very sensitive, so getting it right by trial & error must have taken a lot of persistence. (Once he demonstrate it, physicists were of course able to explain it.) Unfortunately, the inventor got screwed over (or screwed himself, depending on who you ask) on the patent front, and didn't profit from the invention. For details see: "Spin stabilized magnetic levitation" by Martin, Helfinger, & Ridgway, Am. J. Phys. 65, 4, 1997 http://www.physics.ucla.edu/marty/levitron/spinstab.pdf http://www.physics.ucla.edu/marty/levitron/spinstab.pdf