This is known as gravitationally induced decoherence. We don't know if there's any truth to this, but people are seriously working on measuring this stuff in th

This is known as gravitationally induced decoherence. We don't know if there's any truth to this, but people are seriously working on measuring this stuff in the lab. You might like to read what Roger Penrose has to say about it. (Btw, we already know how to combine Maxwell's equations and gravity. This is all classical physics.)