Hal Finney wrote:
> This would seem to indicate that the early universe, despite being
> exceedingly hot and dense by our standards, was not a good environment
> for evolution.
> Without energy differences there is no way for life to exist.
I don't believe this is true. Our kind of life requires energy differences, yes. But the laws of thermodynamics aren't really laws; they're statistical guidelines. There is no physical reason why you can't take tap water and produce electricity and ice cubes; it's just very very improbable. The laws of physics are time-symmetrical (except for state-vector reduction); if the atoms are in the right places with the right velocities, a glass of water can leap from the floor and unshatter.
Energy differentials are a human convention for encoding computations into large ordered groups of particles. But I am ignorant of a reason why computations can't be encoded into single particles bouncing around in a system of uniform temperature. The thermodynamic (as opposed to statistical) definition of entropy is not "complete disorder"; it means "not 'ordered' in the sense of 'having different average temperatures in different places'". In fact, information is directly proportional to entropy. The more information it takes to encode a system, the more mathematically random ("normal") that system is, the more entropy that system has. Ergo, maximally efficient information-processing takes place at uniform temperature.
The question we have to ask is not, "Are there visible computations?", but "Are there computations?" How much computing power would it take to accurately and precisely simulate the Big Bang? If the answer is "infinity", then any computation which has a finite chance of taking place ought to occur. Actually, there are some caveats to that, since there has to be an infinite number of interactions between particles; moreover, there has to be an infinitely long linear sequence of interactions, with each interaction affecting the next interaction.
Anyway, the question isn't whether there are macroscopic computations (of the sort we're used to) taking place, but whether arbitrary computations can be encoded in the physical process of the Big Bang.
-- firstname.lastname@example.org Eliezer S. Yudkowsky http://pobox.com/~sentience/AI_design.temp.html http://pobox.com/~sentience/sing_analysis.html Disclaimer: Unless otherwise specified, I'm not telling you everything I think I know.