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Updated: Aug 7, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Quantum version of free-energy--irreversible-work relations
Wojciech De Roeck1, Christian Maes
1Instituut voor Theoretische Fysica, KU Leuven, B-3001 Leuven, Belgium.
Abstract:
We give a quantum version of the Jarzynski relation between the distribution of work done over a certain time-interval on a system and the difference of equilibrium free energies. The main ingredient is the identification of work depending on the quantum history of the system and the proper definition of various quantum ensembles over which the averages should be made. We also discuss a number of different regimes that have been considered by other authors and which are unified in the present set-up. In all cases, quantum or classical, it is a general relation between heat and time-reversal that makes the Jarzynski relation so universally valid.
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