Spontaneous Lorentz Violation and Baryogenesis

TL;DR

This paper explores how spontaneous Lorentz violation in background fields can generate matter-antimatter asymmetry during thermal equilibrium, proposing models for baryogenesis involving pseudo-Nambu-Goldstone bosons and sphaleron processes.

Contribution

It systematically investigates models of spontaneous Lorentz violation enabling baryogenesis, identifying two distinct scenarios based on field dynamics and energy scales.

Findings

High-energy and electroweak baryogenesis models are possible.

Two scenarios: pseudo-Nambu-Goldstone boson and sphaleron-induced baryogenesis.

Background fields can generate asymmetry in thermal equilibrium.

Abstract

In the presence of background fields that spontaneously violate Lorentz invariance, a matter-antimatter asymmetry can be generated even in thermal equilibrium. In this paper we systematically investigate models of this type, showing that either high-energy or electroweak versions of baryogenesis are possible, depending on the dynamics of the Lorentz-violating fields. We identify two scenarios of interest: baryogenesis from a weak-scale pseudo-Nambu-Goldstone boson with intermediate-scale baryon-number violation, and sphaleron-induced baryogenesis driven by a constant-magnitude vector with a late-time phase transition.