Baryon asymmetry from primordial black holes

Abstract

We propose a new scenario of the baryogenesis from primordial black holes (PBH). Assuming presence of microscopic baryon (or lepton) number violation and a CP violating operator such as ${\partial }_{\alpha }F({\mathcal{R}}_{....})J^{\alpha }$, where $F({\mathcal{R}}_{....})$ is a scalar function of the Riemann tensor, time evolution of an evaporating black hole generates baryonic (leptonic) chemical potential at the horizon; consequently PBH enumerates asymmetric Hawking radiation between baryons (leptons) and anti-baryons (leptons). Though the operator is higher dimensional and largely suppressed by a high mass scale $M_{\ast }$, we show that sufficient amount of asymmetry can be generated for a wide range of parameters of the PBH mass $M_{\mathrm{PBH}}$, its abundance ${\Omega }_{\mathrm{PBH}}$, and the scale $M_{\ast }$.

Comments: 33 pages, 6 figures; published version