Please bear with me. I'm by no means well versed in these matters. I'm merely an interested layman. This question might not even make sense, but, if it doesn't, maybe someone could help me understand why. What I'm wondering is this. If we posit multiple universes -- not in the quantum sense of co-existing in separate dimensions but within the same space; rather, in the more prosaic sense of multiple universes existing side by side in space within this dimension -- would these universes not be expanding towards each other? And if so, what would happen when they collide? As I see it, if our universe is finite, that can only mean that beyond it lie other universes. Separated by vast voids, I suppose. Personally I find it impossible to conceive of how either time or space could be finite, how either could have a beginning or an end. If either does have a beginning or an end, it could only be in some limited sense subjectively important within our humble human perspective.