Is the universe infinite?

I've learned now that when thinking about questions like this one you take a close look at that sign on the door which says, "Abandon common sense all ye who enter here!" In fact I quite like Einstein when he said that common sense is the collection of predudices we acquire before we are 18 years old.

Having said that, I have trouble in understanding how the universe can be infinite. It started off very small. It expanded. The latest evidence indicates that it is currently expanding. So in what sense can it be infinite?

I think universe has same as the circle my dear.Circle is infinite but stay in the limited area.I use information from COBE and hubble only.

Hey mate's that is very interesting question i sometime's ponder on that i believe that the universe is infinite yeah just like a circle no ending and beginning.

I just got into a long discussion with a friend of mine as to whether or not the universe is infinite or finite.

I said it was sort of a mixture of both.Like a sphere inside itself.Or something you see off in the distance,but no matter how fast you run or travel,you'll never get to it.

His argument was that the universe was infinite...that it goes forever with no ends,etc.

basically my whole point was that it was.but shared properties of each infinite and finite.His whole argument was that,"since you can never get to the end of it,that means its infinite."