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A nonequilibrium equality for free energy differences

C. Jarzynski
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Abstract

An expression is derived for the classical free energy difference between two configurations of a system, in terms of an ensemble of finite-time measurements of the work performed in parametrically switching from one configuration to the other. Two well-known equilibrium identities emerge as limiting cases of this result.

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C. Jarzynski. 1996-10-30. A nonequilibrium equality for free energy differences. https://doi.org/10.1103/physrevlett.78.2690

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