A high-density universe basically means that there is enough matter in the universe, packed closely enough to other matter that gravity will eventually begin to slow and reverse the expansion of the universe. The universe will then begin to contract and collapse back in on itself. It will get hotter because of this, but ultimately the universe will go back into a really tiny ball. Then, another big bang will occur, and the process will start over again.
A low-density universe will not have enough matter for gravity to stop the expansion. Two things could happen at this point. The first is heat death. Stars will use up their fuel and die. Solar systems and planets will grow dark and cold . . . and die. The universe will be a cold, dark, dead place. The second thing is matter will simply begin ripping itself apart and seeking an even distribution throughout the universe. Either way, a low-density universe winds up being a cold, dead, dark place.
No comments:
Post a Comment