We’ve not established the rate of expansion, if it’s accelerating, what rate it’s accelerating, or even if space is expanding. It seems likely but not proven or

We’ve not established the rate of expansion, if it’s accelerating, what rate it’s accelerating, or even if space is expanding. It seems likely but not proven or nailed down. Further, it’s not known if it’s possible to manipulate the expansion, such that you could create a local pocket of non expanding space. At the moment galactic space is likely not expanding, and space around black holes wouldn’t expand for an extraordinarily long time. It does seem inevitable, but it also seems that way from our current point of knowledge. Nothing says the story ends with our current understanding.