# Baryogenesis in Lorentz-violating gravity theories

## TL;DR

This paper proposes a new baryogenesis mechanism in Lorentz-violating gravity theories, where vector fields coupled to scalars generate the observed matter-antimatter asymmetry without conflicting with current experimental bounds.

## Contribution

It introduces a novel baryogenesis process in Lorentz-violating gravity models, linking vector-scalar couplings to the generation of baryon asymmetry in the early universe.

## Key findings

- Net $B-L$ generated in early universe
- Baryon-to-photon ratio matches observations
- Model consistent with astrophysical and solar system constraints

## Abstract

Lorentz-violating theories of gravity typically contain constrained vector fields. We show that the lowest-order coupling of such vectors to $\mathrm{U}(1)$-symmetric scalars can naturally give rise to baryogenesis in a manner akin to the Affleck-Dine mechanism. We calculate the cosmology of this new mechanism, demonstrating that a net $B-L$ can be generated in the early Universe, and that the resulting baryon-to-photon ratio matches that which is presently observed. We discuss constraints on the model using solar system and astrophysical tests of Lorentz violation in the gravity sector. Generic Lorentz-violating theories can give rise to the observed matter-antimatter asymmetry without violating any current bounds.