Right now, with the galactic material we can observe, it appears the universe is on a path to a “Big Freeze.” This is a depressing thought, but you have to remember this is speculation. We really just don’t know.
There are currently three categories of models that describe the movement of the universe: Lambda Cold Dark Matter theory, Big Rip, and Big Crunch. These three are centered around the strength of gravity and whether or not it will overpower the expanding universe. Essentially, the Lambda Cold Dark Matter theory, the leading theory, describes a universe where the expansion wins, a universe that expands forever, ultimately ending in a Big Freeze.
Right now, based on our limited observations and knowledge, one of our best guesses is that the universe ends in a Big Freeze. Right now, with what we know, we need more galactic material for this not to be true.
