[smeg]

The problem is you are applying linear Earth-scale concepts of space to the whole Universe.

In reality space (or space-time) is curved - as you approach the "edge" of the universe you actually are traversing a loop around a 4-dimensional hyper-sphere.

The common analogy of an ant on the surface of a balloon is quite effective. As the balloon expands, the distance between points on the surface of the balloon certainly grow and they become further apart. The ant can measure this, see this, but for the life of him, no matter how far he walks, he cant find the "edge of the universe".

Of course it is hard to visualise this analogy when projected into our 4-dimensional universe, but it's the best we've got.

[natep]

No, you do not 'loop around' the universe. It is flat, not a hyper-sphere. The 4th dimension of the universe is time, and not spatial.