ABSTRACT

"The Midlife Crisis of the Cosmos"

With the advent of new space observatories and new instruments
on ground-based telescopes, astronomers have now mapped much
of the star formation and the supermassive black hole accretion
that produces the light of the universe. The emerging consensus
is that the early universe was dominated by a small number of
giant galaxies containing colossal black holes and prodigious
bursts of star formation, while the more recent universe is
surprisingly active in a more dispersed mode---the creation
of stars and the accretion of material into black holes is
being carried out in a large number of medium-size and small
galaxies. I will discuss the observations at many different
wavelengths that have led astronomers to accept that there
has been a vast downsizing that is redistributing cosmic
activity from the large to the small.