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Updated: Jun 8, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Violation of the fluctuation-dissipation theorem in time-dependent mesoscopic heat transport
Dmitri V Averin1, Jukka P Pekola
1Department of Physics and Astronomy, Stony Brook University, SUNY, Stony Brook, New York 11794-3800, USA.
Abstract:
We have analyzed the spectral density of fluctuations of the energy flux through a mesoscopic constriction between two equilibrium reservoirs. It is shown that at finite frequencies, the fluctuating energy flux is not related to the thermal conductance of the constriction by the standard fluctuation-dissipation theorem, but contains additional noise. The main physical consequence of this extra noise is that the fluctuations do not vanish at zero temperature together with the vanishing thermal conductance.
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