1108.1697 (Theo M. Nieuwenhuizen)
Theo M. Nieuwenhuizen
It is assumed that a galaxy starts as a dark halo of a few million Jeans
clusters (JCs), each of which consists of nearly a trillion micro brown dwarfs,
MACHOs of Earth mass. JCs in the galaxy center heat up their MACHOs by tidal
forces, which makes them expand, so that coagulation and star formation occurs.
Being continuously fed by matter from bypassing JCs, the central star(s) may
transform into a super massive black hole. It has a fast $t^3$ growth during
the first mega years, and a slow $t^{1/3}$ growth at giga years. JCs disrupted
by a close encounter with this black hole can provide matter for the bulge.
Those that survive can be so agitated that they form stars inside them and
become globular star clusters. Thus black holes mostly arise together with
galactic bulges in their own environment and are about as old as the oldest
globular clusters. The age 13.2 Gyr of the star HE 1523-0901 puts forward that
the Galactic halo was sufficiently assembled at that moment. The star formation
rate has a maximum at black hole mass $\sim4 \ 10^7M_\odot$ and bulge mass
$\sim5\,10^{10}M_\odot$. In case of merging supermassive black holes the JCs
passing near the galactic center provide ideal assistance to overcome the last
parsec.
View original:
http://arxiv.org/abs/1108.1697
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