Non-Abelian gauge preheating

TL;DR

This paper investigates preheating in inflation models where a scalar field couples to a non-Abelian SU(2) gauge field, demonstrating efficient tachyonic preheating and discussing numerical methods for simulation.

Contribution

It introduces a numerical scheme combining lattice gauge theory with finite difference methods to study non-Abelian gauge preheating in inflation models.

Findings

Significant tachyonic instability enables efficient preheating.

Preheating efficiency is suppressed by increasing the gauge self-coupling.

A detailed numerical implementation for simulating non-Abelian gauge fields during preheating.

Abstract

We study preheating in models where a scalar inflaton is directly coupled to a non-Abelian $SU(2)$ gauge field. In particular, we examine $m^2 \phi^2$ inflation with a conformal, dilaton-like coupling to the non-Abelian sector. We describe a numerical scheme that combines lattice gauge theory with standard finite difference methods applied to the scalar field. We show that a significant tachyonic instability allows for efficient preheating, which is parametrically suppressed by increasing the non-Abelian self-coupling. Additionally, we comment on the technical implementation of the evolution scheme and setting initial conditions.