Black Holes and Their Evolution: Combining Multiwavelength Observations and Theory

It has been over a decade since the discovery that the mass of a central black hole scales with the
properties of its host galaxy. Because of these remarkable scaling relations, the idea that galaxies
and black holes coevolve through some sort of self-regulated feedback has come to dominate scientific
discussion. But do we really understand what the scaling relations are telling us? I will review state
of the field and present recent developments from the observational perspective of the black hole
scaling relations, including our rediscovery of a 1.7e10 solar mass black hole in a galaxy with stellar
mass only 1.2e11 solar masses, discussing how well coevolution models and their alternatives can handle
this.
In addition to coevolution, the scaling relations in the local universe inform the study of formation of
black hole seeds, black hole density functions across cosmic time, and the disputed claims of evolution of
the scaling relations with redshift. I will discuss my theoretical works in these areas as well as my
work on a new tool for using X-ray and radio measurements to measure black hole masses. I will conclude by exploring what important, observational and theoretical questions still need to be answered.