Institute for Advanced Study Astrophysics Seminar

ABSTRACT: Nearly all astronomers now believe that most or all galaxies contain a supermassive black hole, and that many properties of the galaxy are tightly correlated with the mass of the black hole. It is becoming widely accepted that the energy released by these growing black holes probably has a significant impact on the host galaxy and its surroundings, and it has been suggested that this process of "AGN feedback" could solve some outstanding problems in cosmological simulations of galaxy formation. However, many important questions remain unanswered: how do the "seed" black holes form and what are their masses? How is black hole growth triggered and regulated, and what is the physical origin of the correlation between black hole mass and galaxy properties? What is the relationship between star formation and black hole accretion? How, in detail, does the energy released by accreting black holes couple with the gas that surrounds and feeds galaxies? I will address these questions with an overview of recent observational results from deep multi-wavelength surveys, and with predictions from theoretical models and simulations.