Bill, The bit about Alice and Bob being an infinite distance apart was not intended to represent a realistic situation. My intention was to look at the non-feasibility of interchange between finite and infinite, in either direction.

Quote:
We can move relative to another part of spacetime, but obviously we cannot move relative to what we are a part of.


I think we are saying much the same thing, except that you say "obviously we cannot move relative to what we are a part of". I would ask how you know that for certain. It seems obvious, but is it?

There never was nothing.