The Relative Growth of Black Holes and of the Stellar Components of
  Galaxies
  Recent observations indicate that the mass of Supermassive Black Holes
(SMBHs) correlate differently with different galaxy stellar components.
Comparing such observations with the results of "ab initio" galaxy formation
models can provide insight on the mechanisms leading to the growth of SMBHs.
Here we use a state-of-the-art semi-analytic model of galaxy formation to
investigate the correlation of the different galaxy stellar components with the
mass of the central SMBH. The stellar mass in the disc, in the bulge, and in
the pseudo-bulge of galaxies is related to quiescent star formation, to galaxy
interactions, and to the loss of angular momentum following disc instabilities,
respectively. Consistently with recent findings, we find that while the
predicted bulge masses are tightly correlated with the SMBH masses, the
correlation between the latter and the galactic discs shows a much larger
scatter, in particular when bulgeless galaxies are considered. In addition, we
obtain that the predicted masses of pseudo-bulges shows little or
no-correlation with the masses of SMBHs. We track the histories of merging,
star formation, and SMBH accretion to investigate the physical processes at the
origin of such findings within the context of cosmological models of galaxy
formation. Finally, we discuss the effects of variations of our assumed
fiducial model on the results.
