Relativity theory usually describes gravity as being an aetherial warping, but then sticks magnetism into the traditional duality of electric & magnetic force. I’ve read that Einstein modeled his description of gravity after his research into magnetism, although I’ve always seen magnetism described as a force in textbooks until the one cited above.
The idea is this: in a YBCO superconductor levitating over a permanent magnet, where is the force to repel gravity coming from? It’s not coming from gravity, because gravity is not a force but instead a warping of time-space. It’s apparently also not coming from the magnetism itself because that would violate conservation of energy. It can’t levitate forever without energy input coming from someplace, right?
I believe that the truth is this: magnetism is a warping of time-space in the same manner that gravity is, but in a different dimensionality. Therefore, in the above thought experiment levitation is achieved or maintained with no energy-input — it is a warping of time space that creates stable levitation. This also entails that the levitating superconductor is in the lowest-potential state of energy that it can exist in, despite not being in the lowest potential state for either the magnetic or gravitational fields independently.