Related papers: Primordial black hole formation by vacuum bubbles …
We calculate the exact formation probability of primordial black holes generated during the collapse at horizon re-entry of large fluctuations produced during inflation, such as those ascribed to a period of ultra-slow-roll. We show that it…
We study a modification of the primordial black hole (PBH) formation model from axion bubbles. We assume that the Peccei-Quinn scalar rolls down in the radial direction from a large field value to the potential minimum during inflation,…
The Reheating process at the end of inflation is often modeled by an oscillating scalar field which shows a background dust-like behaviour, prompting the analysis of gravitational collapse and black hole formation in this era to be…
Primordial black holes (PBHs) are a viable candidate for dark matter if the PBH masses are in the currently unconstrained "sublunar" mass range. We revisit the possibility that PBHs were produced by nucleation of false vacuum bubbles during…
Independently from the formation mechanism of primordial black holes in the early Universe, their generation is accompanied by a ringdown phase during which they relax to a stationary configuration and gravitational waves under the form of…
We examine the formation and evolution of primordial black holes (PBH's) after hybrid inflation. Our goal is to assess the effects of various theoretical uncertainties on the extrapolation from a given inflation model to a spectrum of…
In this article we investigate the cumulative stochastic gravitational wave spectra as a tool to gain insight on the creation mechanism of primordial black holes. We consider gravitational waves from the production mechanism of primordial…
We summarize our work on the generation of primordial black holes in a type of two-field inflationary models. The key ingredient is a sharp turn of the background trajectory in field space. We show that certain classes of solutions to the…
We show that primordial black holes can be formed in the matter-dominated era with gravity described by the Brans-Dicke theory. Considering an early matter-dominated era between inflation and reheating, we found that the primordial black…
Formation of primordial black holes (PBHs) on astrophysical mass scales is a natural consequence of inflationary cosmology if the primordial perturbation spectrum has a large and negative running of the spectral index as observationally…
Small black holes should have formed in the early Universe if the density contrast was high enough. This article aims at giving a - biased and partial - short overview of the latest breakthroughs in this field. It first deals with tentative…
The possibility that dark matter could be primordial black holes is discussed with an emphasis on the most commonly studied inflationary dynamics that could have produced them.
Primordial black holes (PBHs) may have formed in the early Universe and may account for all or part of the dark matter. In this review, we summarize the current observational constraints on PBHs across the full mass range, highlight…
After the end of inflation, the inflaton field oscillates around a local minimum of its potential and decays into ordinary matter. These oscillations trigger a resonant instability for cosmological perturbations with wavelengths that exit…
We argue that the existence of the cold dark matter is explained by primordial black holes.We show that a significant number of primordial black holes can be formed in an axion-like curvaton model, in which the highly blue-tilted power…
We show that the abundance of primordial black holes, if formed through the collapse of large fluctuations generated during inflation and unless the power spectrum of the curvature perturbation is very peaked, is always dominated by the…
We consider the process of primordial black hole (PBH) formation originated from primordial curvature perturbations produced during waterfall transition (with tachyonic instability), at the end of hybrid inflation. It is known that in such…
We devise a novel mechanism and for the first time demonstrate that the Higgs model in particle physics can drive the inflation to satisfy the cosmic microwave background observations and simultaneously enhance the curvature perturbations…
We performed the detailed analysis of the primordial black hole (PBH) formation mechanism in an axionlike curvaton model with a coupling to inflaton. The phase direction of the complex scalar works as a curvaton and produces enough PBHs to…
Various mechanisms have been suggested for the formation of Primordial Black Holes (PBHs), and this thesis focuses on the standard mechanism based on the critical collapse of cosmological fluctuations. The underlying idea is that during…