Debye mass in de Sitter space

TL;DR

This paper investigates the emergence of Debye mass in de Sitter space and electric fields, revealing it appears only in specific vacuum states and calculating its value through quantum electrodynamics methods.

Contribution

It demonstrates the conditions under which Debye mass arises in de Sitter space, especially in alpha-vacua, and provides explicit calculations for these cases.

Findings

Debye mass appears only in alpha-vacuum in the Expanding Poincare Patch

Debye mass can be computed via direct methods or analytical properties

Electric field case also yields Debye mass calculation

Abstract

We calculate the one-loop contributions to the polarization operator for scalar quantum electrodynamics in different external electromagnetic and gravitational fields. In the case of gravity, de-Sitter space and its different patches were considered. It is shown that the Debye mass appears only in the case of alpha-vacuum in the Expanding Poincare Patch. It can be shown either by direct computations or by using analytical and casual properties of the de-Sitter space. Also, the case of constant electric field is considered and the Debye mass is calculated.