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Name: Unknown
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

If the universe does eventually reverse its expansion and begin to collapse, will the Second Law of Thermodynamics then be reversed so that energy will be required to make any closed system more disordered?

At least not for a long time after it starts to collapse. The second law simply indicates that there are a large number of states available for systems to occupy beyond the initial states and that it is overwhelmingly probable that the system will evolve to occupy these other states. Events far away will not change this.

Sam Bowen

Steven Hawking's "Brief History of Time" provides a good summary of the best guesses on this. The evidence seems to be that the Second Law of Thermodynamics will hold forever, and that the final state of the universe, even if it collapses back on itself, will be much more disordered than the initial state.

Arthur Smith

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