Hk-Neowizard t1_ixed4xs wrote on November 22, 2022 at 8:23 PM

Space might be finite, we don't know, and can't know, since the observable space is all we can talk about in any certain matter (i.e the region of space that we can see or interact with, given the limitation of the speed of light). The observable space is finite.

However infinite space could exist, without there being something "outside" space. It doesn't have to have an edge. That's easy if you consider curved in a higher dimension.

Take the 2D case for simplicity. A 2D creature living on a sheet of A4 paper can't see height, only width and depth. If you roll that sheet into a cylinder, "space" is still finite, but has no edge. You could travel along the circumference forever.

So finite space with no edge is easy, and in fact likely given some observations we made (which are a bit over my head, TBH)

WictImov t1_ixek2zw wrote on November 22, 2022 at 9:08 PM

The closed loop model is a different animal, it would suggest you could end back at your starting point if you travel in one direction far enough (just like going around the world in an airplane). While possible, I am unaware of any evidence that leads us in that direction. I would say the cosmic microwave background suggests otherwise.