Black hole gas in the early universe

TL;DR

This paper explores the behavior of a black hole gas in the early universe within models with extra dimensions, analyzing how black holes form, grow, and interact with radiation under extreme conditions.

Contribution

It introduces a detailed model of black hole dynamics in the early universe, including formation, growth, evaporation, and interactions, considering the effects of extra dimensions.

Findings

Black holes can grow by absorbing radiation and collisions.

The system can follow two distinct evolutionary paths based on initial temperature.

Black hole production and growth significantly influence early universe dynamics.

Abstract

We consider the early universe at temperatures close to the fundamental scale of gravity (M_D << M_Planck) in models with extra dimensions. At such temperatures a small fraction of particles will experience transplanckian collisions that may result in microscopic black holes (BHs). BHs colder than the environment will gain mass, and as they grow their temperature drops further. We study the dynamics of a system (a black hole gas) defined by radiation at a given temperature coupled to a distribution of BHs of different mass. Our analysis includes the production of BHs in photon-photon collisions, BH evaporation, the absorption of radiation, collisions of two BHs to give a larger one, and the effects of the expansion. We show that the system may follow two different generic paths depending on the initial temperature of the plasma.