In this video, scientists from Tel Aviv University demonstrate an interesting phenomenon called “quantum trapping”. The system that they use is comprised of two parts: a superconductor and a permanent magnet. If you put them both together and you get nothing special, but if you cool the superconductor with liquid nitrogen, things get really interesting. The cold distorts the magnetic field to such an extent that the superconductor is trapped in space.
While it would, in theory, be possible to create a hoverboard that levitated via this principal, it wouldn’t be practical. Superconductors aren’t cheap and keeping stuff super-cold with liquid nitrogen is just not practical – and you need the magnets. Still, this is a step in the right direction and way cooler than conventional magnetic levitation.
The video second video explains a little more about the principal of quantum trapping.
And… in case you are wondering why our intrepid scientist was able to handle the disc with his bare hands after it had been sitting in liquid nitrogen, check out the video below – it explains the Leidenfrost Effect.