Fortunatly for you, I study this stuff...I might add some of my own opinions as well, some I am assuming...sort of far-fetched, I don't know if thats the right word for it though.

(Scientific Theory)
The universe is constantly expanding, it will eventually get so big that the universe will not be able to support itself, therefore will collapse. Much like the process when a star becomes a black hole.

(Commentary)
This might suggest that the big bang might start all over again. Creating a new universe, heres a far-fetched conclusion I have made, possibly time starts over again streight from the big bang, it might have continued this cycle for trillions of trillions of years.

Although it is not backed up by anything, this is what I beleve to be true, a guess if you will.