Manifold with boundary

[DDTG Global]

what would the universe look like if its a manifold with boundary? what would it look like at the boundary? and what happens if u try to touch the boundary? is it just a black wall that's unbreakable?

 

[Orodruin]

This would depend on what kind of boundary conditions you impose. As far as we can tell though, there is no evidence whatsoever to imply a boundary.

 

[PeroK]

what would the universe look like if its a manifold with boundary? what would it look like at the boundary? and what happens if u try to touch the boundary? is it just a black wall that's unbreakable?

There's no working model of the universe with a boundary.