Black Holes in Globular Clusters

Texas Tech University

Black holes in globular star clusters are important for a variety of reasons: they may represent the most effective way to produce double black hole mergers that represent the first gravitational wave sources detected; they certainly have a strong impact on the dynamics of stars clusters, and their mergers may represent a process in the early Universe that can lead to the build-up of the seeds for supermassive black holes. For over a generation, it was thought that globular clusters would eject their black holes. Over the past decade, a growing body of evidence has developed that globular clusters do contain black holes of both the accreting and non-accreting variety. I will discuss the theoretical foundations for the existence of these objects, the current observational evidence for them, and the prospects for improving our knowledge of them.