Quantum effects on the evaporation of PBHs: contributions to dark matter

TL;DR

This paper investigates how quantum corrections, specifically the memory burden effect, influence primordial black hole evaporation and their potential role as dark matter candidates, expanding the viable parameter space for such models.

Contribution

It introduces quantum corrections to PBH evaporation rates, demonstrating their impact on dark matter relic abundance and extending PBH lifetime considerations.

Findings

Quantum effects significantly increase PBH lifetimes.

A wide parameter space allows PBHs to account for dark matter.

Decay of PBHs can contribute to the dark sector.

Abstract

We compute the relic abundance of dark matter in the presence of Primordial Black Holes (PBHs) beyond the semiclassical approximation. We take into account the quantum corrections due to the memory burden effect, which is assumed to suppress the black hole evaporation rate by the inverse power of its own entropy. Such quantum effect significantly enhances the lifetime, rendering the possibility of PBH mass $\lesssim 10^{9}$ g being the sole dark matter (DM) candidate. However, Nature can not rule out the existence of fundamental particles such as DM. We, therefore, include the possibility of populating the dark sector by the decay of PBHs to those fundamental particles, adding the contribution to stable PBH whose lifetime is extended due to the quantum corrections. Depending on the strength of the burden effect, we show that a wide range of parameter space opens up in the initial PBH mass and fundamental dark matter mass plane that respects the correct relic abundance.