$S$-matrix description of nonequilibrium finite-temperature systems

We consider the ‘`inclusive" {(}"partial"{\rm)} method for describing nonequilibrium dissipative systems at the early {\rm(}kinetic{\rm)} evolution stage, when the temperature distribution is nonuniform. We formulate the perturbation theory in terms of space–time-local temperature Green’s functions and derive the Liouville equation for the one-particle partition function.