AGN and QSOs in the eROSITA All-Sky Survey -- Part II: The large-scale
  structure
  The four-year X-ray all-sky survey (eRASS) of the eROSITA telescope aboard
the Spektrum-Roentgen-Gamma satellite will detect ~3 million active galactic
nuclei (AGN) with a median redshift of z~1 and a typical luminosity of
L_(0.5-2.0 keV) ~ 10^(44) erg/s. We show that this unprecedented AGN sample,
complemented with redshift information, will supply us with outstanding
opportunities for large-scale structure research. For the first time, detailed
redshift- and luminosity-resolved studies of the bias factor for X-ray selected
AGN will become possible. The eRASS AGN sample will not only improve the
redshift- and luminosity-resolution of these studies, but will also expand
their luminosity range beyond L_(0.5-2.0 keV) ~ 10^(44) erg/s, thus enabling a
direct comparison of the clustering properties of luminous X-ray AGN and
optical quasars. These studies will dramatically improve our understanding of
the AGN environment, triggering mechanisms, the growth of supermassive black
holes and their co-evolution with dark matter halos.
  The eRASS AGN sample will become a powerful cosmological probe. It will
enable detecting baryonic acoustic oscillations (BAOs) for the first time with
X-ray selected AGN. With the data from the entire extragalactic sky, BAO will
be detected at a >~10sigma confidence level in the full redshift range and with
~8sigma confidence in the 0.8 < z < 2.0 range, which is currently not covered
by any existing BAO surveys. To exploit the full potential of the eRASS AGN
sample, photometric and spectroscopic surveys of large areas and a sufficient
depth will be needed.
