Bulk viscosity and deflationary universes

TL;DR

This paper investigates the role of bulk viscosity in entropy generation during inflation, highlighting conditions where it cannot account for particle production in certain phases.

Contribution

It identifies specific scenarios where bulk viscosity fails to describe particle production during coherent field oscillations in inflationary models.

Findings

Bulk viscosity cannot always explain entropy generation during inflation.

Certain conditions prevent bulk viscosity from modeling particle production.

The study clarifies limitations of bulk viscosity in inflationary cosmology.

Abstract

We analyze the conditions that make possible the description of entropy generation in the new inflationary model by means of a nearequilibrium process. We show that there are situations in which the bulk viscosity cannot describe particle production during the coherent field oscillations phase.