Abstract: | The first observations of gravitational waves emitted by merging binary black holes demonstrated the existence of black holes more massive than ever observed in our Galaxy. Future observations with ground-based interferometers such as Advanced LIGO and Virgo will probe the mass and spin distributions of black holes in various galactic environments. Since stellar-mass black holes form at the end of the nuclear lifetimes of massive stars, these measurements will provide a new tool for stellar evolution studies. In the first part of this talk I will describe a cosmological framework for modeling the population of black holes and its evolution with redshift. I will then show which features of stellar evolution models can be constrained with future observations of binary black hole mergers. In the second part of this talk I will discuss the prospects of detecting the stochastic gravitational wave background from super-massive black hole binaries that form when galaxies merge. In particular, I will argue that even under the most conservative assumptions the signal from super-massive black holes will be detected in the coming years by Pulsar Timing Array experiments and possibly also by the space-based interferometer LISA, which is currently in its design stage. |