Microscopic nonequilibrium structure in quantum fields and H-functions

Exact dynamical models for entropy production and entropy flow are introduced by means of the complex spectral representation and illustrated by using a simple conservative Hamiltonian system for multileveled atoms coupled to an external time-dependent field. The dynamical form of the H-function is introduced corresponding to the Friedrichs model coupled with the external periodic force. The external force destroys the monotonicity of the H-function evolution and leads to a model for the “entropy flow”. As the result of competition between the dissipation inside the system and the regeneration of the excited states due to the external field, there appears a steady structure of the emitted field around the unstable particle, which corresponds to the “dissipative structure” and is intrinsic to the system as it does not depend on its initial preparation. The behavior of the H-function is investigated for the “velocity inversion experiment”.