REHEATING AND THERMALIZATION IN A SIMPLE SCALAR MODEL

We consider a simple model for the Universe reheating, which consists of a single self-interacting scalar field in Minkowskian space-time. M aking use of the existence of an additional small parameter proportion al to the amplitude of the initial spatially homogeneous field oscilla tions, we show that the behavior of the field dan be found reliably. W e describe the evolution of the system from the homogeneous oscillatio ns to the moment when thermalization is completed. We argue that some properties found for this model may be the common features of realisti c theories.