Curious_dog

On 2/28/2021 at 1:57 PM, Halc said:

...A universe described in its entirety by Minkowski spacetime (infinite uniform distribution of superclusters, not receding from each other, but evolving in place, so gravity wells, but not on the largest scale) would admit this time-like Killing vector field since the matter distribution wouldn't change significantly over time. The density in particular would be fixed, and in such a universe, my argument might be meaningful, but not in this universe.

Can't we make amends? Can the average gravitational potential inside our Universe within some finite time frame be computed on an assumption the Universe is frozen within this time frame and the Killing vector field can be (approximately) defined? If the Universe were not expanding, and we could treat it as having finite dimension and uniform matter distribution on macro scale, we would get the simple expression for the potential relative to the Universe boundaries (or "center"). 

I wonder if the assumption of the infinite Universe leads to the accelerated expansion as to get density reduction with the distance, resulting in the finite gravitational energy within the Universe (which will likely be constant throughout it on macro scale, so no force).