Title: Local Black Holes, The Inverse Dinosaur Problem
Data from the Hubble Space Telescope and other sources shows that nearly every nearby "normal" galaxy has a supermassive black hole in the mass range 10^6 to 10^9 solar masses. The mass density of these objects in these objects is consistent with the cosmic density of quasars and the X-ray background. These objects represent a major revision in our thinking about the formation of galaxies and the evolution of quasars. They impinge on many issues: i) the thermodynamics of the interstellar medium in protogalaxies, and therefore star formation. ii) the number and redshift - distribution of very luminous gravitational wave sources. iii) the dynamics of galaxy mergers. iv) the structure of present-day galaxies. There are also key areas of uncertainty: i) the extrapolation of scaling relations for bh mass and galaxy parameters is controversial at low and high mass. ii) the epoch of formation of bh is unknown. iii) it is possible that there are large numbers of uncounted bh.
Douglas Richstone is Professor and Chair of Astronomy at the University of Michigan, where he has worked since 1980. He has held brief concurrent appointments at the National Observatory of Japan, the Institute for Advanced Study and the Institute for Theoretical Physics at UC Santa Barbara, and as a Guggenheim Fellow.
Richstone received a B.S. with honors in Astronomy from Caltech and a Ph.D. in Astrophysics from Princeton University in 1975. His most active current research activities include dynamics of galaxy centers and the demographics, formation and evolution of massive black holes. He is the leader of the "Nukers", an international collaboration of 15 scientists studying the nuclei of galaxies, and a member of the LISA (Large Interferometry Space Antenna) Science Team. He maintains interests in the estimation of cosmological parameters and formation and evolution of clusters of galaxies.
Title: How Black Holes Shape their Cosmic Environments
In addition to radiation, accreting supermassive black holes produce copious outflows of fast plasma and energetic particles. These forms of kinetic energy output can profoundly affect a black hole's environment, and may even regulate the growth of both the black hole and its galactic host. Thanks to recent Chandra and XMM observations, clusters of galaxies are proving to be valuable laboratories for studying this interaction. I will discuss what we have learned recently about energetic feedback from black holes to their surroundings, from both observations and theoretical modeling.