Large Squeezing Behavior of Cosmological Entropy Generation

TL;DR

This paper analyzes how entropy is generated during cosmological particle creation, showing it depends linearly on the squeeze parameter and varies with coarse graining choices.

Contribution

It provides a general calculation of entropy generation due to matter field fluctuations in cosmology, highlighting the linear relationship with the squeeze parameter.

Findings

Entropy generation is linear in the squeeze parameter.

Dependence of entropy on coarse graining criteria is discussed.

Results apply to a broad class of initial states.

Abstract

We consider the generation of entropy when particle pairs are created at a cosmological level. Making a reduction via the particle number basis, we compute the classical limit for the entropy generation due to the evolution of the matter field fluctuations (squeeze transformation), obtaining that it is linear in the squeeze parameter for a general class of initial states. We also discuss the dependence of the generated entropy on the coarse graining criteria.