Related papers: On the Primordial Black Hole Mass Function for Bro…
We propose a novel mechanism where Primordial Black Hole (PBH) dark matter is formed much later in the history of the universe between the epoch of Big Bang Nucleosynthesis (BBN) and Cosmic Microwave Background (CMB) photon decoupling. In…
Primordial black holes (PBH) can form in the early Universe from peaks of the primordial curvature perturbations. The statistics of the peaks determines the abundance of PBHs, and is related to the amplitude of the primordial curvature…
Non-perturbative quantum gravity effects might allow a black-to-white hole transition. We revisit this increasingly popular hypothesis by taking into account the fundamentally random nature of the bouncing time. We show that if the…
Assuming that primordial black holes compose a fraction of dark matter, some of them may accumulate at the center of galaxy and perform a prograde or retrograde orbit against the gravity pointing towards the center exerted by the central…
It is shown that a mechanism of PBH formation from high-baryon bubbles with log-normal mass spectrum naturally leads to the central mass of the PBH distribution close to ten solar masses independently of the model details. This result is in…
Primordial black holes (PBHs) are of special interest because of the crucial role of quantum effects in their formation and evaporation. This means that they provide a unique probe of the early universe, high-energy physics and quantum…
Primordial Black Holes (PBHs) might have formed in the early Universe due to the collapse of density fluctuations. PBHs may act as the sources for some of the gravitational waves recently observed. We explored the formation scenarios of…
Primordial black holes are analytically and numerically discussed based on the extended McVittie spacetime solution. By assuming that dark matter and radiation are the only sources of energy accreted by the forming central object, it is…
We examine how future gravitational-wave measurements from merging black holes (BHs) can be used to infer the shape of the black-hole mass function, with important implications for the study of star formation and evolution and the…
The formula for the initial mass spectrum of primordial black holes (PBHs), which can be used for a general case of the scale dependent spectral index, and for a wide class of models of the gravitational collapse, is derived. The derivation…
In this chapter we first describe the early history of primordial black hole (PBH) research. We then discuss their possible formation mechanisms, including critical collapse from inflationary fluctuations and various types of phase…
We consider the constraints on the fraction of dark matter in the universe in the form of primordial black holes taking into account the crucial role of accretion which may change both their mass and mass function. We show that accretion…
Primordial black holes (PBHs) could be formed if large perturbations are generated on small scales in inflation. We study a toy inflation model with a local minimum. The curvature perturbations are enhanced when the inflaton passes through…
Scalar condensates with large expectation values can form in the early universe, for example, in theories with supersymmetry. The condensate can undergo fragmentation into Q-balls before decaying. If the Q-balls dominate the energy density…
Primordial black holes (PBHs) in the mass range $10^{17} - 10^{23}~{\rm gm}$ are considered as possible dark matter candidates as they are not subject to big-bang nucleosynthesis constraints and behave like cold dark matter. If PBHs are…
We consider constraints on primordial black holes (PBHs) in the mass range $( 10^{-18}\text{-}10^{15} )\,M_{\odot}$ if the dark matter (DM) comprises weakly interacting massive particles (WIMPs) which form halos around them and generate…
Primordial black holes can represent all or most of the dark matter in the window $10^{17}-10^{22}\,$g. Here we present an extension of the constraints on PBHs of masses $10^{13}-10^{18}\,$g arising from the isotropic diffuse gamma ray…
A primordial black hole (PBH) is thought to be made of the regular matter or ordinary mass ($M$) only, and hence could have already been decayed due to the Hawking radiation if its initial ordinary mass were $\lesssim 5 \times 10^{11}$ kg.…
In this note we point out that primordial black holes could be much shorter lived than usually assumed if there is a large hidden sector of particles that only interacts gravitationally with the particles of the standard model. The…
We investigate the ambiguity of the novel mass function of primordial black holes, which has succeeded in identifying the black hole mass in a given configuration of fluctuations, due to the choice of window function of smoothed density…