The Second Rule of Thermodynamics says that the entropy of a <b>closed or isolated</b> system increases. Earth is an open system in which entropy decreases; Earth receives low-entropy light energy from the Sun and radiates high-entropy heat energy into cold space. That simple exchange is sufficient to explain the evolution of life on Earth.
In the bigger picture, the question is whether the universe is an open or closed system. Most people assume it is closed, but there really is no sound basis for that assumption. We don’t know if the universe is finite in size, mass, energy or time. I believe that, if the universe is infinite in any dimension, then it may be either open or closed; the term “indeterminate” comes to mind.
Suppose just for a moment that BB is more or less valid, but time is infinite. In that case, perhaps the processes that occurred shortly after the BB might have been just as complex as those we see now—but on a vastly shorter scale of time and distance. The processes we are familiar with may be inconceivably brief in the eyes of some extremely distant future generation of beings—maybe a google years from now. They might think of the age of galaxies as we think of the first googolth of a second after the beginning. If that is the case, then the universe is not winding down, but merely shifting gears—the number of gears in the transmission being infinite in both the past and the future.
[Addendum; a few minutes after the original post.] I suspect that the measure of entropy depends on the time scale of the observer. Let’s suppose the total entropy in the universe increases at a linear rate. In extremely general terms (a zillion meaning many orders of magnitude): If observer A lives a zillion times earlier than observer B, and A’s perception of time is a zillion times faster than observer B’s, then A will measure a zillion times more entropy in his universe than observer B’s estimate of how much entropy existed in A’s time. Therefore, the total entropy measured by A is equal to that measured by B.
I mentioned in another thread recently that some alleged “black holes” are consuming matter, which spirals inward in a disk, and spewing jets of anti-matter at roughly ½ c perpendicular to the disk. Anti-matter seems to act like ordinary matter in reverse time. From that, I propose Phil’s Second Rule of Anti-thermodynamics: In a closed anti-matter system, from the viewpoint of an ordinary-matter observer, entropy decreases. Therefore, if the universe is a closed system, consisting of ordinary matter and anti-matter in a dynamic equilibrium, then total entropy of the universe may fluctuate, but the long term total entropy of the universe tends toward a constant value.
