C. Rodriguez Colloquium: Growing Big Black Holes in Dense Star Clusters

Last month marked the 10-year anniversary of GW150914, the first direct detection of gravitational waves by the LIGO Collaboration. While surprising at the time, the past decade has unveiled an entire population of 30+ solar mass black holes detected both through gravitational waves and astrometric observations by Gaia. In this talk, I will describe how massive and old star clusters, such as the globular clusters in the Milky Way, are an ideal production site for these systems, and why we think they contribute a significant fraction of binaries detected to date. I will show how the birth conditions of these star clusters can create massive black holes---from 30 solar mass binaries to the ever elusive intermediate-mass black holes. Understanding the origin of these systems can help us understand the formation of globular clusters themselves, and may even let us constrain nuclear processes in the cores of massive stars.