TallyMan wrote:
As, I remember, the physics depended on how much matter is in the universe. If there is enough then it is finite but unbounded. To put that in common language picture the universe as the surface of a beach ball. The ball is gradually getting bigger. If you draw a straight line on the ball you eventually get back to the starting point. Similarly with travel in a finite but unbounded universe, it has no edge. If you could keep travelling you would eventually get back to where you started.
The picture may be more complex than that now though with dark matter, dark energy and membrane theory all being thrown into the scientific theorem melting pot.
It appears only complex for our minds: I like to refer a bit to I. Kant, that our model of the world is shaped as well as with sensual perception of the world as well as with our pre-set ideas of the world. The origin of those ideas is relative easy to explain with the task this model had to serve in struggle of surviving on the surface of the earth.
If we recall this and realize that this model was never tested evolutionary to provide any inside into the structure of space, time and matter it would be very surprising when this structure would follow our pre-set ideas of the world at all.
We are struggling here with an ape's brain and an abstract reasoning machine combined into one body and mind.