Meissner effect - Wikipedia, the free encyclopedia
This has been known about since
1933. High temperature superconductors made this sort of levitation capable with liquid nitrogen cooling in the late 80's.
Lack of progress in this research field has kept transition temperatures of superconductors from making any major strides in the last two decades.
The one hope is that, with enough work, a room temperature superconductor can be found and processed in quantity. Everything gets faster, better, cheaper once that happens. Electricity can be transmitted long distances without losses. Supercomputers would become more efficient, becoming faster without increase in thermal problems. Levitating trains, mass driver orbital launch platforms, superconducting quantum interference devices used as super-detailed MRI machines that could be wearable, portable devices instead of the room-sized machines we have now, you name it....
One of the many parts of science that, fundamentally, is very sound, very possible, and just requires funding. There is nothing magic or impossible about finding more high temperature superconductors that make all these things possible. It just takes time, people, and lots of money. The benefits of finding such materials would take years to pay off, but would do so in ways that would change our world.