Correlation Functions of Massless Interacting Scalar Fields in de Sitter Space

TL;DR

This paper investigates the behavior of correlation functions for a massless scalar field with quartic interactions in de Sitter space, revealing that two-loop corrections lead to a dynamical mass for low momentum modes while high momentum modes remain massless.

Contribution

It provides a detailed analysis of two-loop corrections and their resummation, showing how they induce a dynamical mass for low momentum modes in de Sitter space.

Findings

High momentum modes remain massless.

Low momentum modes develop a dynamical mass.

Two-loop corrections are significant and lead to complex structures.

Abstract

We examine the behavior of correlation functions for a massless scalar field in de Sitter space with a quartic interaction. We find that two-loop corrections are relevant, and that the resummation of these corrections generates a complicated structure whereby high momentum modes stay massless while low momentum modes develop a dynamical mass.