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Fluctuation theorems: Work is not an observable

Peter Talkner·Eric Lutz·Peter Hanggi
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Abstract

The characteristic function of the work performed by an external time-dependent force on a Hamiltonian quantum system is identified with the time-ordered correlation function of the exponentiated system's Hamiltonian. A similar expression is obtained for the averaged exponential work which is related to the free energy difference of equilibrium systems by the Jarzynski work theorem.

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Peter Talkner, Eric Lutz, Peter Hanggi. 2007-05-23. Fluctuation theorems: Work is not an observable. https://doi.org/10.1103/physreve.75.050102

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