Department of Astrophysical Sciences

Supermassive black holes (BHs) are a ubiquitous component of nearby galaxies, and we believe that BH growth plays an important role in galaxy evolution.  I discuss three projects, each designed to elucidate the role of BH growth in galaxy evolution.  I begin with a new look at local BH-bulge scaling relations provided by a large sample of spiral galaxies containing megamaser disks.  The resulting exquisite BH mass measurements provide strong evidence that BHs evolve differently in low-mass spiral galaxies.  Second, studies of BH demographics as a function of cosmic time provide complementary constraints on the coevolution of BHs and galaxies. I discuss ongoing efforts to use active galaxies as a tracer of the BH population at high redshift. Finally, I present an exciting new sample of dual BHs uncovered with Magellan.