KINETIC-THEORY FOR PARTICLE-PRODUCTION

Recently, the phenomenological description of cosmological particle pr oduction processes in terms of effective viscous pressures has attract ed some attention. Using a simple creation rate model we discuss the q uestion to what extent this approach is compatible with the kinetic th eory of a relativistic gas. We find the effective viscous pressure app roach to be consistent with this model for homogeneous spacetimes but not for inhomogeneous ones.