Instanton interaction in de Sitter spacetime

TL;DR

This paper calculates the first corrections to vacuum decay rates in de Sitter spacetime caused by finite instanton separation effects, considering the influence of the cosmological horizon.

Contribution

It introduces a novel calculation of instanton interaction effects on vacuum decay rates in de Sitter space, extending the dilute instanton gas approximation.

Findings

First correction to decay rate derived

Dependence on theory parameters and cosmological constant analyzed

Results refine understanding of vacuum stability in de Sitter space

Abstract

Because of the presence of a cosmological horizon the dilute instanton gas approximation used for the derivation of the Coleman-De Luccia tunneling rate in de Sitter spacetime receives additional contributions due to the finite instanton separation. Here I calculate the first corrections to the vacuum decay rate that arise from this effect and depend on the parameters of the theory and the cosmological constant of the background spacetime.