Free energy

A thermodynamic potential that constrains useful work under specified conditions.

Key question

Why does time have an arrow?

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Find an example, an application and a limit. Explain the concept without using its name, then compare your explanation with a primary source.

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Claims to examine

  • Macroscopic entropy increase requires statistical and boundary-condition assumptions in addition to microscopic dynamics.

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  • Why does time have an arrow?

    Connect energy, entropy, statistical ensembles and nonequilibrium processes without confusing microscopic laws with macroscopic trends.

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