Resumo:
In this work, we will calculate the Feynman propagator of a scalar field with mass M at
finite temperature T in the Einstein universe, which is a static space-time. The field will
be arbitrarily coupled to the curvature (i.e., the coupling parameter of the scalar field
with curvature will have an arbitrary value). From the renormalized propagator, we will
determine the stress-energy-momentum tensor of the scalar field and, as a consequence,
the corresponding thermodynamics. This study is of interest because the non-stationary
(i.e., dynamic) universe appears to be a "succession of Einstein universes", starting with
the primordial universe. Our results will be compared to the existing literature.