Now we all know the 2nd law of thermodynamics says that the entropy of the universe increases in physical processes. We also all know the universe is expanding. Now suppose the [tex]\Omega[/tex] value led to a big crunch situation. It would seem intuitive to me, that the moment right after the big bang, should have the same entropy value as the moment right before the 'big crunch', however the 2nd law says that the moment right before the 'big crunch' will have a higher entropy.(adsbygoogle = window.adsbygoogle || []).push({});

So the question is; does the 2nd law apply in a contracting universe?

Note that I am only familiar with the [tex]dS=\frac{dQ}{T}[/tex] definition of entropy, so please explain any more advanced (ie stat mech) definitions clearly.

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# Entropy in a contracting universe?

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