What lies outside of the boundaries of space. I find the problem in this question is our knowledge, we have a prior belief that we are exist inside space, this belief that doesn’t based on any evidence, so I think before we asking, what lies outside of space? We must first ask, are the objects lying inside space or outside of it?
I think if objects are exist outside of space, it will suffer from superposition or uncertainty in position depending on the distance from space or how far is it from space.