Primordial seeds of supermassive black holes

TL;DR

This paper explores the hypothesis that primordial black holes formed during inflationary epochs could serve as the initial seeds for supermassive black holes observed in galactic centers, especially at high redshifts.

Contribution

It proposes a model where multiple inflation periods enhance density perturbations, leading to primordial black holes of about 10^5 solar masses that could seed supermassive black holes.

Findings

Primordial black holes of ~10^5 solar masses can form from inflationary perturbations.

Such black holes could explain the early existence of supermassive black holes.

The model links inflationary dynamics to black hole seed formation.

Abstract

Supermassive black holes exist in the centers of galaxies, including Milky Way, but there is no compelling theory of their formation. Furthermore, observations of quasars imply that supermassive black holes have already existed at some very high redshifts, suggesting the possibility of their primordial origin. In a class of well-motivated models, inflationary epoch could include two or more periods of inflation dominated by different scalar fields. The transition between such periods of inflation could enhance the spectrum of density perturbations on some specific scale, which could lead to formation of primordial black holes with a very narrow range of masses of the order of 10^5 solar masses. These primordial black holes could have provided the requisite seeds for the observed population of supermassive black holes.