Think of space as a giant bag and in this giant bag are lots of fire crackers (representing stars). lets say a fire cracker goes off (supernova) ...if it is close to a side then it most likely will break a hole in the bag (the bag is representing space or the universe)...the universe would be exposed to the outside. Lets say it was not near a side, but in the middle...then the bag would be unharmed...right? Anyway what I am trying to say is that if a black hole doesn't occur at the farthest points of our universe then how can they supposably lead to other places???