(Submitted February 10, 1999)
I have been pondering this question now for an inordinate amount of
time. The second law of thermodynamics states, if I can remember
correctly, that entropy will increase with time, where entropy = the
amount of disorder in a system. With increasing disorder, there is
inherently less energy that can be used to do useful work. With this
inherent lack of useful energy, is it then feasible that in some point
in time, the universe will reach a state of thermal equilibrium, where
there is nothing more than a collection of protons evenly spaced apart
and all moving at the same speed?
Basically yes. That state is called 'the heat death of the Universe'.
(The protons will all have decayed, but the Universe will consist of
smaller particles all drifting at random and getting more and more distant
from each other as the Universe expands).
for a more recent view of this.
David Palmer and Samar Safi-Harb
for Ask an Astrophysicist