Gravitational Baryogenesis and Dark Matter from Light Black Holes

TL;DR

This paper proposes a unified mechanism where primordial black holes generate baryon asymmetry and dark matter through Hawking radiation, offering a novel two-component dark matter model that aligns with cosmological observations.

Contribution

It introduces a new scenario linking black hole evaporation to baryogenesis and dark matter production, including a two-component dark matter model that satisfies observational constraints.

Findings

Black hole evaporation can produce baryon asymmetry via Hawking radiation.

A two-component dark matter model explains both baryon asymmetry and dark matter abundance.

The scenario evades constraints on individual dark matter candidates.

Abstract

We study a scenario in which the baryon asymmetry is created through Hawking radiation from primordial black holes via a dynamically-generated chemical potential. This mechanism can also be used to generate the observed dark matter abundance, regardless of whether or not the black holes fully evaporate. In the case that evaporation ceases, the observed dark matter abundance is generically comprised of both relic black holes and an asymmetric dark matter component. We show that this two-component dark matter scenario can simultaneously account for the observed baryon asymmetry and the cosmological dark matter, a possibility which evades constraints on either individual candidate.