COSMOLOGY WITH ADIABATIC MATTER CREATION

The influence of matter creation processes on the dynamics of the earl y universe is investigated within a phenomenological approach. By usin g a balance law for the particle number in addition to the familiar re lations for viscous fluid cosmologies the whole dynamics is given expl icitly in terms of the particle production rate. We argue that a suffi ciently high particle production rate gives rise to an inflationary be haviour with finite values of temperature and density at the beginning of the hydrodynamic period of the universe.