Related papers: Magnetic field generation from primordial black ho…
In this paper, we show that if passive fluctuations are considered, primordial black holes (PBHs) can be easily produced in the framework of single-field, slow-roll inflation models. The formation of PBHs is due to the blue spectrum of…
Primordial magnetic fields possibly generated in the very early universe are one of the candidates for the origin of magnetic fields observed in many galaxies and galaxy clusters. After recombination, the dissipation process of the…
A group of massive galaxies at redshifts of $z\gtrsim 7$ have been recently detected by the James Webb Space Telescope (JWST), which were unexpected to form so early within the framework of standard Big Bang cosmology. In this work, we…
Possible influence of primordial black hole (PBH) evaporations on cosmic microwave background (CMB) is investigated. The spectrum distortions of CMB from the black-body spectrum are described by the chemical potential $\mu$ and the Compton…
We investigate the abundance of Super-Massive Black Hole (SMBH) seeds in primordial galaxy halos. We explore the assumption that dark matter halos outgrowing a critical halo mass M_c have some probability p of having spawned a SMBH seed.…
We present a well-tested, theoretically supported empirical relation that helps decipher the origins, growth, and properties of SMBHs (supermassive black holes). Based on theoretical considerations and analysis of mass (MBH) versus age (t)…
If primordial black holes (PBHs) form directly from inhomogeneities in the early Universe, then the number in the mass range $10^5 -10^{12}M_{\odot}$ is severely constrained by upper limits to the $\mu$ distortion in the cosmic microwave…
The primordial black hole (PBH) abundance evaluated by the conventional Press-Schechter (PS) probability distribution is shown to be equivalent to the high-peak limit of a special point-like peak statistics via unphysical dimensionality…
The abundance of primordial black holes (PBHs) in the mass range $0.1 - 10^3 M_\odot$ can potentially be tested by gravitational wave observations due to the large merger rate of PBH binaries formed in the early universe. To put the…
The recent observations of supermassive black holes (SMBHs) at high redshift challenge our understanding of their formation and growth. There are different proposed pathways to form black hole (BH) seeds, such as the remnants of the first…
A primordial black hole (PBH) is interesting to people for its ability of explaining dark matter as well as supermassive astrophysical objects. In the normal inflation scenario, the generation of PBHs usually requires an enhanced power…
We study the effect of dark matter (DM) being encapsulated in primordial black holes (PBHs) on the power spectrum of density fluctuations $P(k)$; we also look at its effect on the abundance of haloes and their clustering. We allow the…
This is the second paper in a series aimed at modeling the black hole (BH) mass function, from the stellar to the (super)massive regime. In the present work we focus on (super)massive BHs and provide an ab-initio computation of their mass…
The origin of our universe's cosmological magnetic fields remains a mystery. In this study, we consider whether these magnetic fields could have been generated in the early universe by a population of charged, spinning primordial black…
The probability of primordial black hole (PBH) formation is known to be boosted during the Quantum Chromodynamics (QCD) crossover due to a slight reduction of the equation of state. This induces a high peak and other features in the PBH…
We reinspect the calculation for the mass fraction of primordial black holes (PBHs) which are formed from primordial perturbations, finding that performing the calculation using the comoving curvature perturbation $\mathcal{R}_{c}$ in the…
We show that the merger of oscillons results in a broad spectrum of the oscillon mass. A huge number of oscillon samples obtained from numerical lattice simulations reveal that the oscillon mass distribution has an exponential tail in a…
We calculate the primordial black hole (PBH) mass spectrum produced from a collapse of the primordial density fluctuations in the early Universe using, as an input, several theoretical models giving the curvature perturbation power spectra…
We constrain the mass abundance of unclustered primordial black holes (PBHs), formed with a simple mass distribution and subject to the Hawking evaporation and particle absorption from the environment. Since the radiative flux is…
Recently, the pulsar timing array (PTA) collaborations, including CPTA, EPTA, NANOGrav, and PPTA, announced that they detected a stochastic gravitational wave background spectrum in the nHz band. This may be relevant to the cosmological…