I'm going to over simplify here on go out on a ledge.... A small part of quantum physics involves a phenomenon where one particle (quark) imitates another particles movement (status) regardless of it's point in the universe.
And that is the very particle that holds the secret (or some of) about time/space travel because of it's ability to be fluid in it's existance. (or at least it's detectable presence)
I suspect that it always exists, just where or when is the question.
At the very least it holds some pretty telling secrets about reality as we know it.