[justaskin]

Well, if the universe encompasses everything, why do we talk about it expanding or decreasing?? Surely that can't happen, since there's nothing greater than the universe to compare its expansion to, and if it expands then everything else will expand and we won't be able to see the difference.

So what do they mean about expanding if that can't really happen?

I am continually puzzled that we can except the theories of Einstein and others without question.Very complicated mathematics but we look at a simple maths sum 1/0 and say it can't happen or it has no meaning.
With regards the universe could it be that the universe is infinite it's just the stuff in it that is expanding.
For an example of infinity in every day use.If I place two mirror's  so they face each other do the image in each not go to infinity.If we could get down to the subatomic level of the mirror would not the image still exist.

Everything can be infinite.
Take a distance, any distance, half it, half it again and then..
until you run out of breath or numbers.

Also the same if we continually double the number.If you think about it I suppose no matter how large or small a number you can think of there is still an infinate distance between that
and infinity.

Cheers
justaskin