Nonperturbative infrared effects for light scalar fields in de Sitter space

TL;DR

This paper investigates nonperturbative infrared effects on light scalar fields in de Sitter space using the 2PI effective action, revealing a curvature-induced mass and symmetry restoration.

Contribution

It applies the 2PI formalism to analyze nonperturbative effects in scalar fields in de Sitter space, highlighting new insights into mass generation and symmetry behavior.

Findings

Infrared effects induce a curvature-dependent mass.

Nonperturbative effects restore broken Z_2 symmetry.

Calculated effective potential and physical mass.

Abstract

We study the phi^4 scalar field theory in de Sitter space using the 2PI effective action formalism. This formalism enables us to investigate the nonperturbative quantum effects. We use the mean field and gap equations and calculate the physical mass and effective potential. We find that nonperturbative infrared effects on de Sitter space produce a curvature-induced mass and work to restore the broken Z_2 symmetry.