Derivation of a two-generator framework of nonequilibrium thermodynamics for quantum systems

Starting from the quantum description of isolated systems on the microscopic level we derive the two-generator formulation of nonequilibrium thermodynamics by means of the projection-operator technique. As a generalized canonical ensemble is employed, we obtain a convenient starting point for practical calculations in nonequilibrium thermodynamics; in particular, also in the classical limit. All dynamical material properties are contained in a canonical nonequilibrium correlation. However, the generalized canonical approach is inappropriate for systems with large fluctuations; possible steps toward a suitable generalization for quantum systems are discussed.