Exploring the high-redshift PBH-$\Lambda$CDM Universe: early black hole
  seeding, the first stars and cosmic radiation backgrounds
  We explore the observational implications of a model in which primordial
black holes (PBHs) with a broad birth mass function ranging in mass from a
fraction of a solar mass to $\sim$10$^6$ M$_{\odot}$, consistent with current
observational limits, constitute the dark matter component in the Universe. The
formation and evolution of dark matter and baryonic matter in this
PBH-\LambdaCDM~Universe are presented. In this picture, PBH DM mini-halos
collapse earlier than in standard \LambdaCDM, baryons cool to form stars at
$z\sim15-20$, and growing PBHs at these early epochs start to accrete through
Bondi capture. The volume emissivity of these sources peaks at $z\sim20$ and
rapidly fades at lower redshifts. As a consequence, PBH DM could also provide a
channel to make early black hole seeds and naturally account for the origin of
an underlying dark matter halo - host galaxy and central black hole connection
that manifests as the $M_{\rm bh}-\sigma$ correlation. To estimate the
luminosity function and contribution to integrated emission power spectrum from
these high-redshift PBH DM halos, we develop a Halo Occupation Distribution
(HOD) model. In addition to tracing the star formation and reionizaton history,
it permits us to evaluate the Cosmic Infrared and X-ray Backgrounds (CIB and
CXB). We find that accretion onto PBHs/AGN successfully accounts for the
detected backgrounds and their cross-correlation, with the inclusion of an
additional IR stellar emission component. Detection of the deep IR source count
distribution by the JWST could reveal the existence of this population of
high-redshift star-forming and accreting PBH DM.
