high on universe wrote:
I hear physicists discussing the vast size of the expanding universe but has anyone ever demonstrated our universe has a border or edge? It seems impossible to discuss an expansion of anything if you can't delineate its borders.
If there was a big bang (which is by far the accepted theory), there is an edge to the universe. If there was no big bang, then there may or may not be an edge to the universe.
There is an edge to the *observable* universe by big bang theory, but whether the universe is infinite (beyond what is observable) or finite (ie. wrapping around on itself) is a different question.