Related papers: Evolution of Primordial Black Holes in Loop Quantu…
The next generation of electromagnetic and gravitational wave observatories will open unprecedented windows to the birth of the first supermassive black holes. This has the potential to reveal their origin and growth in the first billion…
General relativity successfully describes space-times at scales that we can observe and probe today, but it cannot be complete as a consequence of singularity theorems. For a long time there have been indications that quantum gravity will…
With detections of quasars powered by increasingly massive black holes (BHs) at increasingly early times in cosmic history over the past decade, there has been correspondingly rapid progress made on the theory of early BH formation and…
Primordial black holes are black holes that may have formed from density fluctuations in the early universe. It has been theorized that black holes slowly evaporate. If primordial black holes of initial mass of $10^{14}$g were formed, their…
We investigate the formation of primordial black holes in curvaton models of inflation, where the curvature perturbation is not only generated by the inflaton but also by a light scalar field (the curvaton) that decays after inflation.…
For primordial black holes (PBHs) to form a considerable fraction of cold dark matter, the required amplitude of primordial scalar perturbations is quite large ($P_{\zeta}(k) \sim 10^{-2}$) if PBH is formed in radiation epoch. In alternate…
Quantum gravity may shed light on the prehistory of the universe. Quantum corrections to gravity affect the dynamics of the expansion of the universe. Their influence is studied on the example of the exactly solvable quantum model. The…
We study fluctuations and correlations between spacial regions, generated by the primordial quantum gravitational phase of the universe. We do so by a numerical evaluation of Lorentzian amplitudes in Loop Quantum Gravity, in a…
Primordial black holes (PBHs) are a compelling dark matter candidate and a unique probe of small-scale cosmological fluctuations. Their formation is usually attributed to large positive curvature perturbations, which collapse upon Hubble…
Using the $\delta N$ formalism we calculate the one-loop correction to the large-scale power spectrum of the curvature perturbation in the standard scenario where primordial black holes are formed in the early universe thanks to a phase of…
We investigate primordial black hole formation in the matter-dominated phase of the Universe, where nonspherical effects in gravitational collapse play a crucial role. This is in contrast to the black hole formation in a radiation-dominated…
This work investigates the formation of primordial black holes within a radiation fluid with an anisotropic pressure. We focus our attention on the initial conditions describing cosmological perturbations in the super horizon regime, using…
We study the formation of primordial black holes when they are generated by the collapse of large overdensities in the early universe. Since the density contrast is related to the comoving curvature perturbation by a nonlinear relation, the…
The Primordial Black Holes (PBHs) are gradually involved into consideration as the phenomenon having reliable basis. We discuss here the possibility of their agglomeration into clusters that may have several prominent observable features.…
In theories with a broken discrete symmetry, Hubble sized spherical domain walls may spontaneously nucleate during inflation. These objects are subsequently stretched by the inflationary expansion, resulting in a broad distribution of…
The spontaneous creation of primordial black holes in a violently expanding Universe is a well studied phenomenon. Based on quantum gravity arguments, it has been conjectured that the early Universe might have undergone a lower dimensional…
Primordial Black Holes (PBHs) have not been experimentally detected so far, but their existence would provide important insights about the early Universe and serve as one of the possible candidates of dark matter (DM). In this work, we…
We discuss the possibilities for primordial black holes (PBHs) to grow via the accretion of dark matter. In agreement with previous works, we find that accretion during the radiation-dominated era does not lead to a significant mass…
The primordial black hole (PBH) formation is studied in light of the inflating curvaton. The typical scale of the PBH formation is determined by curvaton inflation, which may generate PBH with $10^{14}\mathrm{g}\le M_\mathrm{PBH}\le…
Evolution of a cluster of primordial black holes in the two-body relaxation approximation based on the Fokker-Planck equation is discussed. In our calculation, we consider the self-gravitating cluster with a wide range of black holes masses…