Speaker
Hyunggyu Park
(Korea Institute for Advanced Study)
Description
Equilibrium is characterized by its fundamental properties such as the detailed balance, the
fluctuation-dissipation relation, and no heat dissipation. Based on the stochastic thermodynamics,
we show that these three properties are equivalent to each other in conventional Langevin thermal
systems with microscopic reversibility. Thus, a conventional steady state has either all three
properties (equilibrium) or none of them (nonequilibrium). In contrast, with velocity-dependent
forces breaking the microscopic reversibility, we prove that the detailed balance and the fluctuationdissipation
relation mutually exclude each other and no equivalence relation is possible between any
two of the three properties. This implies that a steady state of Langevin systems with velocitydependent
forces may maintain some equilibrium properties but not all of them. Our results are
illustrated with a few example systems.
Primary author
Hyunggyu Park
(Korea Institute for Advanced Study)
Co-author
Hyunn Keun Lee
(SungkyunKwan University)