I have no idea what is on the edge of the universe however surfaces of free floating fluids take the shape of a sphere when no forces act on it, I would say it?s a sphere but I really have no idea, as to what happened before it, I look to the universe expanding. . Will it stop? Will it teeter for a moment and reverse back to the centre. . In a sort of "Big Crunch" will it then explode as all the matter and energy collide like a giant particle accelerator this is pushing physics to its most mind boggling limits.
Back to the question what?s on the other side. . Is there even a theory or school of thought to challenge? It would be interesting to be on the great verge in a space ship only to pass through . . .