Kinetic theory for particle production
نویسندگان
چکیده
Recently, the phenomenological description of cosmological particle production processes in terms of effective viscous pressures has attracted some attention. Using a simple creation rate model we discuss the question to what extent this approach is compatible with the kinetic theory of a relativistic gas. We find the effective viscous pressure approach to be consistent with this model for homogeneous spacetimes but not for inhomogeneous ones. PACS numbers: 98.80.Hw, 05.20.Dd, 04.40.Nr, 95.30.Tg ∗Present address: Fakultät für Physik, Universität Konstanz, PF 5560 M677, D-78434 Konstanz, Germany
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