Supermassive black holes (BHs) with masses of ~ 106 to 109
Solar masses are believed to live at the centers of most large galaxies.
I review the observed demographics and inferred evolution of BHs found by
spatially resolved kinematic measurements. Tight correlations between
BH mass and the mass and velocity dispersion of the host-galaxy bulge have
led to the belief that BHs and bulges coevolve by regulating each other's
growth. New results replace this simple story with a richer and more
plausible picture in which BHs correlate differently with different galaxy
components. This allows us to refine our picture of BH-galaxy coevolution.
Coevolution clearly is important in some objects (giant elliptical galaxies)
and not in others (disk galaxies like our Milky Way). A major area of galaxy
research is to investigate why some galaxies actively form stars whereas
others are "red and dead". Many lines of research now converge on a
unified picture of the quenching of star formation in the nearby Universe.
The main quenching agents appear to be (1) starbursts and BH energy feedback
in galaxy collisions and mergers that involve cold gas and (2) hot,
X-ray-emitting gas in giant galaxies and in clusters of galaxies.
This talk is an update of Kormendy & Ho 2013, ARA&A, 51, 511.
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