: Black Holes: : I have been reading recently a book about the theory of Einstein and a book about black holes and I would like to put the next question : : Your first definition of black holes, considering a singularity is opposite to your introduction of imaginary time; in the theory of Einstein I could however not find a proof that nothing could move faster than c, so my question is if it is possibly that a black hole is a mass that is moving quicker than light ( and therefore we can't see it ). Is this opposite with other principles you examined. : Thank you for an answer.

I've read about imaginary time also, From what I recall, it is similar to imaginary numbers in math. I think Stephen is refering to some hypothetical particle that could move faster than c not the black hole itself.