Description
Primordial Black Holes (PBHs) can be produced even in the early matter
dominated Universe due to collapses of regions which have large
curvature perturbation produced by inflation.
I will review the current status of formations and evolutions of PBHs
in the early matter dominated Universe. If time allows, I will also
mention cosmological and astrophysical constraints on PBHs with
introducing my own bounds on PBHs in terms of polarization of Cosmic
Microwave Background photons due to cosmological accretions onto PBHs
(arXiv:1707.04206 [astro-ph.CO]), cosmological/gamma-ray/cosmic-rays
bounds on evaporating PBHs (arXiv:0912.5297 [astro-ph.CO]), Higgs
phenomenology (arXiv:1708.02138 [hep-ph]), stochastic GWs
(arXiv:1903.05924 [astro-ph.CO], arXiv:1903.05924 [astro-ph.CO]), dark
matter (arXiv:1802.06785 [astro-ph.CO]), ultra-compact mini halo
formations (arXiv:1712.08820 [astro-ph.CO] and arXiv:1905.04477
[astro-ph.CO]), clustering (arXiv:1909.04053 [astro-ph.CO]) and so on.
