Whether the universe would expand forever ot collapse on itself has been an issue in astronomy for some time. Recent calculations have concluded that a colapse is not possible.

Quote Originally Posted by SadisticNature View Post
Why does the universe have to begin or end?

If time is cyclical it could just go expand-collapse forever without beginning or end.

Our understanding of time is very limited.

Much the way when you stand on a sphere (i.e. the earth) the surface around you appears to be flat and you might think the entire earth was flat, from a specific point in time it appears that the past and future are distinct things, but what if 10,000,000,000 years in the future (from a local perspective) the universe has finished its collapse, expands under the previous initial conditions and the same process repeats. We are back to the same point in time, you are still standing there 'making' the exact same decision. (Note this model assumes predestination over free-will).

I might even have a very bad way of explaining something like this as no one has been able to test anything like this. My point is merely that first cause is hardly an established principle of absolute truth on infinite time scales.