Speaker : Maximilien BARBIER / Lecturer in Theoretical Physics/Applied Mathematics University of the West of Scotland, United Kingdom

Abstract :

Thermodynamics in its standard form applies to systems that are at equilibrium. It hence says very little about the processes that may drive a system from one equilibrium state to another. Describing such processes is the goal of nonequilibrium thermodynamics.

The study of nonequilibrium systems has originally been restricted to phenomena that occur near equilibrium. This approach yielded important results such as the celebrated Onsager-Casimir reciprocity relations or the fluctuation-dissipation theorem. Close to equilibrium, the response of the system depends linearly on the constraints that drive it out of equilibrium. This linear behavior breaks down as the system is driven farther away from equilibrium. Alternative methods are thus required to treat such nonlinear regimes. To this regard, exact results have been obtained in the form of the so-called fluctuation relations (or fluctuation theorems) whose main strength is to remain valid arbitrarily far from equilibrium.
In this talk, I will introduce some of the main ideas that underly nonequilibrium thermodynamics and discuss how fluctuation relations can be used to access the nonequilibrium properties of general systems. In particular, I will quantify the impact of a fluctuation relation on the full statistics of the nonequilibrium currents that take place in the system.

Pour tout contact :

Rodolfo JALABERT : rodolfo.jalabert@ipcms.unistra.fr

Dietmar WEINMANN : dietmar.weinmann@ipcms.unistra.fr