Black holes as antimatter factories

TL;DR

This paper proposes that low-mass black holes can act as antimatter factories by acquiring positive charge, leading to electron-positron pair production and positron emission due to vacuum instability.

Contribution

It introduces a novel mechanism where charged black holes produce antimatter by exploiting vacuum instability at the horizon for black holes below 10^{20} g.

Findings

Black holes can acquire positive charge through accretion.

For black holes below 10^{20} g, electric fields can trigger pair production.

Black holes can convert protons into positrons, acting as antimatter factories.

Abstract

We consider accretion of matter onto a low mass black hole surrounded by ionized medium. We show that, because of higher mobility of protons than electrons, the black hole would acquire positive electric charge. If the black hole's mass is about or below $10^{20}$ g, the electric field at the horizon can reach the critical value which leads to vacuum instability and electron--positron pair production by the Schwinger mechanism. Since the positrons are ejected by the emergent electric field, while electrons are back--captured, the black hole operates as an antimatter factory which effectively converts protons into positrons.