Transport Properties

Abstract

In contrast to thermal equilibrium where the state of the system is characterized by given mean values of the conserved quantities as energy and particle number, the non-equilibrium state of a system is characterized by additional mean values of macroobservables. In the hydrodynamic description of a non-equilibrium state, such additional observables are the currents of particles, energy and momentum, respectively, which are determined by the corresponding equations of continuity for the conserved quantities. In the kinetic description, the mean values of the occupation numbers, i.e. the distribution functions for the different species, are considered as relevant observables.