Long-Lived Time-Dependent Remnants During Cosmological Symmetry Breaking: From Inflation to the Electroweak Scale

TL;DR

This paper demonstrates that during cosmological symmetry breaking in an expanding universe, long-lived, time-dependent field configurations called oscillons can form spontaneously, persist for extended periods, and significantly contribute to the universe's energy density.

Contribution

The study provides the first detailed numerical analysis showing the formation and longevity of oscillons during symmetry breaking in an expanding spacetime, including both scalar and non-Abelian gauge fields.

Findings

Oscillons contribute about 1.2% of the universe's energy density in scalar field models.

Expansion enhances oscillon lifetimes via parametric resonance effects.

In SU(2) models, oscillons account for approximately 4% of the energy density.

Abstract

Through a detailed numerical investigation in three spatial dimensions, we demonstrate that long-lived time-dependent field configurations emerge dynamically during symmetry breaking in an expanding de Sitter spacetime. We investigate two situations: a single scalar field with a double-well potential and the bosonic sector of an SU(2) non-Abelian Higgs model. For the single scalar, we show that large-amplitude oscillon configurations emerge spontaneously and persist to contribute about 1.2% of the energy density of the universe. We also show that for a range of parameters, oscillon lifetimes are enhanced by the expansion and that this effect is a result of parametric resonance. For the SU(2) case, we see about 4% of the final energy density in oscillons.