What would happen if you put a magnetic ball inside a sphere of opposite magnetism, would it float in mid air?

Answer 1

You have hit right on the work of years of scientists at Livermore. The have been trying to hold Hydrogen right in the center of a magnetic field and heat it to the point it loses mass and becomes Helium. Fission its called. Fission would be possible if we had a crucible that would melt down and would hold Hydrogen as you know!! So the thing thts used is the magnetic field as you describe above.

And they have had some sucess in holding a magnetic material in dead center of the magnetic field.

Most of this work is supersensitive material so about all that is know for sure is that it has been done .