The formation of the first black holes and their host halos

The first massive astrophysical black holes likely formed at high redshifts (z ≳ 10) at the centers of low mass (∼106 M⊙) dark matter concentrations. These black holes grow by mergers and gas accretion, evolve into the population of bright quasars observed at lower redshifts, and eventually leave the supermassive black hole remnants that are ubiquitous at the centers of galaxies in the nearby universe. The astrophysical processes responsible for the formation of the earliest seed black holes are poorly understood. The purpose of this review is to describe theoretical expectations for the formation and growth of the earliest black holes within the general paradigm of hierarchical cold dark matter cosmologies, and to summarize several relevant recent observations that have implications for the formation of the earliest black holes.