Abstract

The Advanced LIGO gravitational-wave detector has just reported the discovery of the first direct detection of gravitational waves confirming Einstein’s Theory of General Relativity in its extreme limit. The sources of these gravitational waves were merging relatively massive stellar-mass black holes that were much more massive than had been predicted before. In this talk I will summarize some of the models for the formation of such massive black-hole binaries, in particular the model proposed by our group (Marchant et al. 2016), which involves the homogeneous evolution of two massive stars in a very close binary. The model makes specific predictions about the mass distribution and the mass ratio of such black-hole mergers. It also predicts that the most massive black-hole mergers can be detected with aLIGO throughout a large fraction of the observable Universe, allowing us to test the theory of massive stars throughout most of the history of the Universe with implications for other enigmatic events such as gamma-ray bursts and superluminous supernovae.