Primordial Black Holes is currently considered a candidate for the dark matter. Still, to give realistic and reliable predictions about their production and abundance, we need to accurately infer the initial conditions that can lead those black holes to be procured. In that sense, numerical simulations of PBH formation are generally essential. In this talk, I will describe how to accurately...
Primordial Black Holes (PBHs) can form in the very early universe and can be associated with numerous cosmological and astrophysical signatures. We examined the production of large curvature perturbations that may lead to PBH formation in the early universe, in particular during the preheating phase that follows after inflation. At this stage, non-perturbative phenomena lead to the exponential...
We discuss the calculation of the power spectrum of scalar perturbations in the presence of stochastic source terms, providing insight on the expected outcome based on analytical approximations. We then focus on the case of warm inflation. In this scenario, the coupling of the inflaton to light fields during inflation leads to the former dissipating part of its energy into a thermal bath. The...
I discuss why stochastic effects are important in PBH formation and how they lead to spiky profiles for the curvature perturbation. When using the compaction function to set a collapse criterion, this can lead to a large enhancement of PBH abundance.
How small-scale enhanced scalar fluctuations influence large scales, for instance, the one probed by the CMB, has recently been the object of an intense debate. In this context, I will discuss how one-loop diagrams from small-scale modes may -only apparently- lead to scale invariant corrections at large scales.
I will then discuss ways to have resonant IR cascades, namely cases where loop...
Observational constraints have closed off all but one mass-window for primordial black holes making up all of the dark matter, and there are some specific conditions required for their production in the first place. However, they remain a tantalising dark matter candidate because they require no new beyond the standard model particles and they would additionally provide a lot of information...
Spherical collapse is assumed in most of the works on PBH formation from the primordial curvature perturbation. According to the peak theory[1], sufficiently high peaks of a Gaussian random scalar field statistically have spherical symmetric shapes in the homogeneous and isotropic universe, which guarantees the above assumption. However, the PBH formation is related to highly non-linear regime...
To prove that primordial black holes are dark matter, various
frequencies of gravitational waves will need to be observed in the
future. I will explain some aspects of the theory and new methods for
observing high frequency gravitational waves.
Current constraints suggest the primordial black holes(PBHs) in mass windows $10^{17}-10^{23}$ gm are potential dark matter candidates. It has been argued that the PBHs less than $10^{15}$ gm would have evaporated by now. These analyses assume black holes are in an asymptotically flat space-time. However, realistic black holes are surrounded by local mass distributions and they are embedded in...
