Entropy production and time asymmetry in nonequilibrium fluctuations

TL;DR

This paper experimentally investigates the time-reversal symmetry in nonequilibrium fluctuations, demonstrating that the difference in dynamical entropies equals thermodynamic entropy production in two physical systems.

Contribution

It provides experimental validation that the difference in standard and time-reversed entropies corresponds to thermodynamic entropy production in nonequilibrium systems.

Findings

Entropy production equals the difference in dynamical entropies.

Time-reversal symmetry is broken in nonequilibrium fluctuations.

Experimental results confirm theoretical predictions.

Abstract

The time-reversal symmetry of nonequilibrium fluctuations is experimentally investigated in two out-of-equilibrium systems namely, a Brownian particle in a trap moving at constant speed and an electric circuit with an imposed mean current. The dynamical randomness of their nonequilibrium fluctuations is characterized in terms of the standard and time-reversed entropies per unit time of dynamical systems theory. We present experimental results showing that their difference equals the thermodynamic entropy production in units of Boltzmann's constant.