Effect of finitetemperature quantum fields on the early universe
Abstract
The finitetemperature effect of a quantized conformally invariant scalar field in a closed RobertsonWalker universe is studied. The general solution is characterized by one parameter ξ = Ta which measures the radiation content of the universe. In the hightemperature limit it reduces to the FischettiHurtleHu solution where the universe expands linearly in cosmic time near the singularity. In the lowtemperature limit, it reduces to a Starobinskyde Sitter type solution where the singularity is avoided in an exponential expansion. Several characteristic functional dependences of ξ(t) are used to illustrate possible entropy generating processes. The finitetemperature formalism thus provides a unifying framework for the description of the interplay of vacuum and radiation energy and their combined effect on the state of the early universe.
 Publication:

Physics Letters B
 Pub Date:
 July 1981
 DOI:
 10.1016/03702693(81)902367
 Bibcode:
 1981PhLB..103..331H