Bubble-nucleation rates for cosmological phase transitions

TL;DR

This paper estimates bubble-nucleation rates during cosmological phase transitions, focusing on the pre-exponential factor using a real coarse-grained potential, and discusses implications for the Higgs-boson mass and electroweak transition.

Contribution

It provides approximate analytical expressions for the pre-exponential factor in bubble-nucleation rates and introduces a method to determine the coarse-graining scale for high-temperature phase transitions.

Findings

Saddle-point approximation is reliable for metastability bounds on Higgs-boson mass.

Saddle-point approximation breaks down for the electroweak phase transition.

A method to determine the coarse-graining scale in phase transition studies.

Abstract

We estimate bubble-nucleation rates for cosmological phase transitions. We concentrate on the evaluation of the pre-exponential factor, for which we give approximate analytical expressions. Our approach relies on the use of a real coarse-grained potential. We show how the coarse-graining scale can be determined in the studies of high-temperature phase transitions. We discuss the metastability bound on the Higgs-boson mass and the electroweak phase transition. We find that the saddle-point approximation is reliable in the first case and breaks down in the second case.