Cosmic microwave background limits on accreting primordial black holes

Abstract

The LIGO observation of black hole merger has revivified interest in the idea whether primordial black holes might comprise some or all of the dark matter. The authors scrutinize the impact of primordial black holes on the CMB, analytically calculating spherical accretion onto black holes. The paper provides stringent constraints on models purporting to connect dark matter to primordial black holes.