Primordial Black Hole Clusters and their Evolution

TL;DR

This paper explores the formation and evolution of primordial black hole clusters originating from phase transitions in the early universe, potentially serving as seeds for active galactic nuclei.

Contribution

It introduces a novel scenario where PBH clusters form from phase transitions involving symmetry breaking during inflation, and studies their subsequent evolution.

Findings

PBH clusters can form from collapsing closed walls during phase transitions.

The evolution of these PBH clusters has specific dynamical properties.

Such clusters could influence early galaxy formation processes.

Abstract

A possibility of pregalactic seeds of the Active Galactic Nuclei can be a nontrivial cosmological consequence of particle theory. Such seeds can appear as Primordial Black Hole (PBH) clusters, formed in the succession of phase transitions with spontaneous and then manifest breaking of the global U(1) symmetry. If the first phase transition takes place at the inflationary stage, a set of massive closed walls may be formed at the second phase transition and the collapse of these closed walls can result in formation of PBH clusters. We present the results of our studies of the evolution of such PBH Clusters.