Dynamics of condensation in out-of-equilibrium systems

par Martin Evans (University of Edinburgh)

jeudi 17 sept. 2015, 11:00 → 12:00 Europe/Paris

Auditorium (Annecy-le-Vieux)

It is a central challenge of statistical physics to describe systems out-of-equilibrium, which are not described by usual Boltzmann statistics and which may exhibit unexpected behaviour. In this talk I will discuss a simple model of interacting classical particles hopping between sites of a one-dimensional lattice, but with rates that do not obey detailed balance and thus generate a nonequilibrium state. Real-space condensation is the phenomenon whereby a finite fraction of the particles are typically found at a single site in the limit of a large system size. I'll show how and why condensation arises and how it is related to large deviations of sums of random variables. I'll also discuss a variation of the model in which the condensate moves rapidly through the system and in which the relaxation time to the stationary state decreases to zero for large system size. This provides a first example of instantaneous gelation in a spatially extended system.