It’s hard for me to comprehend the idea that space never ends. Is there really no boundary to space? How do scientists know this?

Question

It’s hard for me to comprehend the idea that space never ends. Is there really no boundary to space? How do scientists know this?

In: Planetary Science

Answer 1

We don’t know this. But think of it another way, (edit adding in this part to be more clear) *if it is a flat universe with no curvature to bend back around*, and if the universe does end, what’s past the boundary then? By definition if something is past the boundary, then that something would also be part of the universe. Even if it’s nothing, then it’s still a vacuum that would be part of the universe. So having a boundary doesn’t make sense.