相关论文: Primordial black holes from the preheating instabi…
Primordial black holes (PBHs) can be produced by the perturbations that exit the horizon during inflationary phase. While inflation models predict the power spectrum of the perturbations in Fourier space, the PBH abundance depends on the…
Black hole relics are of significant interest in cosmology and theoretical physics. In this work, we consider tiny primordial black holes (PBHs) ( $M_{\text {PBH }} \lesssim 10^7 \mathrm{~g}$ ) which are generated soon after the end of…
We review the formalism of primordial black holes (PBHs) production and show that the mass variance at horizon crossing has been systematically overestimated in previous studies. We derive the correct expression. The difference is maximal…
A variety of scenarios for early-universe cosmology give rise to a population of primordial black holes (PBHs) with a broad spectrum of masses. The evaporation of PBHs in such scenarios has the potential to place the universe into an…
Here, generation of Primordial Black Holes (PBHs) from quartic potential in the presence of a tiny bump in non-canonical inflationary model has been inquired. It is demonstrated that, a viable inflationary era can be driven through the…
We propose a two-field model where the inflaton $\chi$ is non-minimally coupled to the instanton $\phi$. By choosing an appropriate coupling function, we realize the scenario where the difference of the values of potential between false…
We propose a new single field inflation model in which the usual slow-roll inflation is joined to a new period of slow-climb and slow-roll inflation through a short intermediate non-inflationary phase. We then show that primordial curvature…
The local primordial density fluctuations caused by quantum vacuum fluctuations during inflation grow into stars and galaxies in the late universe and, if they are large enough, also produce primordial black holes. We study the formation of…
Primordial black holes (PBHs) may be part of the dark matter. It is shown here that PBHs form more easily during cosmic phase transitions. For approximately scale-invariant primordial curvature fluctuations the PBH mass function may…
A broad range of single field models of inflation are analyzed in light of all relevant recent cosmological data, checking whether they can lead to the formation of long--lived Primordial Black Holes (PBHs) as candidate for dark matter. To…
Supersymmetric extensions of the standard model generically predict that in the early universe a scalar condensate can form and fragment into Q-balls before decaying. If the Q-balls dominate the energy density for some period of time, the…
We consider several early Universe models that allow for production of large curvature perturbations at small scales. As is well known, such perturbations can lead to formation of primordial black holes (PBHs). We briefly review the today's…
With the basic $\alpha$-attractor potentials, we investigate an inflationary regime in the high-$k$ limit, where the cosmological perturbation breaks down due to large enhancement in the scalar power spectrum and generation of large…
Primordial Black Holes (PBHs) that form from the collapse of density perturbations are more clustered than the underlying density field. In a previous paper, we showed the constraints that this has on the prospects of PBH dark matter. In…
Primordial black holes (PBHs) produced in the early Universe have attracted wide interest for their ability to constitute dark matter and explain the compact binary coalescence. We propose a new mechanism of PBH production during…
In this paper, we investigate the production of primordial black holes (PBHs) during the radiation-dominated era. The collapse of significant density perturbations originating from large primordial scalar fluctuations generated during…
In this paper, we propose a model in which a spectator field non-minimally couples to an inflaton field and the power spectrum of the perturbation of the spectator field at small scales is dramatically enhanced by the sharp feature in the…
Primordial black holes (PBHs) are one of the candidates to explain the gravitational wave (GW) signals observed by the LIGO detectors. Among several phenomena in the early Universe, cosmic inflation is a major example to generate PBHs from…
We study the possibility of production of primordial black holes (PBHs) from bubble collisions during a first-order phase transition. While typical colliding bubbles are small and irrelevant for PBH production, we find that those that can…
We study perturbations of a complex scalar field during reheating with no self-interaction in the regime $ \mu \gg H$, when the scalar field has a fast oscillatory behaviour (close to a pressure-less fluid). We focus on the precise…