Can supconductors levitate without magnets?

[Everten P.]

The title may be misleading but I want to know. Can a superconductor use quantum levitation with the earths magnetic field to lift something like a car (If it was big enough)? And if there is a way can you show me a formula?

[Z-Man]

Not sure what you mean by "quantum levitation" (Meissner efffect?), but if you want to essentially do maglev without a track, the answer is no. To levitate magnetically you need inhomogeneous medium-strong external fields. The geomagnetic field is too weak and locally too homogeneous. In a homogeneous external field, a magnet can only produce torque, not force.

[Winter Man]

Flux pinning, he means. But still no, the Earth's field is too weak. No City of Columbia for you today, I'm afraid.

I mean, you might be able to produce a metamaterial out of superconductor that works in weaker fields than currently, but still not as weak as Earth's.

Edited July 1, 2014 by Winter Man