What you are speaking of is a highly controversial theory that still does not have a shred of proof to it. It is mostly used by creationists to explain how Earth is only 6000 years old. On a side note, though the energies required are pretty much prohibitive, Gravity appears to travel instantly. While this is virtually impossibe to test easily, they do indicate that, for example, if the sun disappered and was somehow taken away, we would be immediatly thrown out of our orbit, DESPITE the fact that we would not know that the sun was gone for over a full 8 minutes. Unfort, how to use that in any way to travel through space is another matter entirely.