: : : How can it be proved that the universe is curved? What possible evidence is there. : : There have been theories that the universe is warped instead. : : How can a wormhole exist if the universe is warped?

: Evidence of the curvature of space would be similar to that of curvature of the earth. For example, ships heading out to sea sink into the horizon. If the curvature of space were sufficient, then there should be a 3 (or 4?) dimensional equivalent that could be applied to space. What that test would be I couldn't say though.

The curvature of the universe would be very hard to verify because it is billions of times bigger than the earth, hence the curvature is minutely small. So small in fact that it would almost be impossible to detect. It is known that graviational fields curve spactime, and it is thought that gravity waves exist. But to detect these gravity waves requires equipment sensitive to less than the radius of an atom. And these waves would be significantly significantly greater than the general curvature of the universe.