Conservative ensembles for nonequilibrium lattice-gas systems
Abstract Book of the XXIII IUPAP International Conference on Statistical Physics, Genova, Italy, (9-13 July 2007)Abstract
The aim of this talk concerns the construction of ensembles in which the particle number is conserved for lattice-gas systems described by a master equation. We will focus on nonequilibrium systems in which particles are created and anihilated on the sites of a lattice. Such systems are defined by a stochastic dynamics and not by a Gibbs probability distribution as is the case of systems in thermodynamic equilibrium. For the latter there is a standard procedure for the passage from one ensemble to another that involves the existence of a Hamiltonian. However, for irreversible systems with a stochastic dynamics such procedure does not apply. We show here how to construct kinetic ensembles for these systems such that the number of particle is conserved. These conservative ensembles can then be used to study phase transitions and critical phenomena particularly discontinuous phase transitions.