On Thermalization in de Sitter Space

TL;DR

This paper analyzes the thermalization process in de Sitter space, estimating a characteristic time scale that allows for non-thermal deviations during inflation and exploring implications for finite quantum systems.

Contribution

It provides a new estimate for the thermalization time in de Sitter space from two perspectives, linking it to broader concepts like Poincaré recurrence.

Findings

Thermalization time in de Sitter space is of order R^3/l_{pl}^2.

Longer thermalization times permit non-thermal deviations during inflation.

The study connects thermalization time to quantum recurrence phenomena.

Abstract

We discuss thermalization in de Sitter space and argue, from two different points of view, that the typical time needed for thermalization is of order $R^{3}/l_{pl}^{2}$, where $R$ is the radius of the de Sitter space in question. This time scale gives plenty of room for non-thermal deviations to survive during long periods of inflation. We also speculate in more general terms on the meaning of the time scale for finite quantum systems inside isolated boxes, and comment on the relation to the Poincar\'{e} recurrence time.