The formation and feeding of supermassive black holes in
galactic centers  Wolfgang J. Duschl1, Peter A. Strittmatter2 1
Institut für Theoretische Astrophysik, Universität Heidelberg,
Germany 2 Steward Observatory, The University of Arizona,
Tucson, AZ, USA  E-mail contact:  Normal galaxies like ours, and
(mildly) active ones, like Seyfert galaxies, have typically
smaller central black holes than quasars. We argue that this is
mainly due to the merger history of the different types of
(active) galaxies. We present model calculations which indicate
that for the formation of the most massive black holes (10^9
M_sun or more) a major merger is required while less massive
ones are formed through normal accretion in a galactic center.
As a consequence of this, the formation of the most massive
black holes is a very fast process which occurs preferentially
in the young Universe, while for the evolution of a black hole
as in the center of our galaxy, most of the Hubble time is
needed. Finally, we will discuss the imp