We show that a broad power spectrum—modeled as a plateau between infrared and ultraviolet scales—results in a bimodal mass function, with the dominant peak corresponding to heavy PBHs associated with the infrared scale.
This result, based on compaction function statistics, significantly impacts overproduction bounds on the power spectrum amplitude, underscores the need for further...
Accurate predictions of correlators of the primordial curvature perturbation are critical for connecting inflationary models to cosmological observations. Numerical methods employing differential equations, such as the transport approach, have been extensively used to compute the evolution of these correlators.
In this talk, I will present a novel numerical implementation of the transport...
In this talk I will discuss scalar fields in cosmology. Specifically, the impact they can have on early universe thermodynamics and primordial black holes.
In scalar field dark matter models, virialized halos form condensed central cores known as solitons. We extend this idea to the reheating phase of the early universe, a critical period that sets the stage for the emergence of structure after inflation. We study the formation of primordial black holes (PBHs) from the gravitational collapse of virialized configurations arising during this era....
I will present a new mechanism of primordial black hole formation via an interrupted phase transition during the early matter-dominated stage of reheating after inflation. In reheating, induced by the decay of a pressureless fluid dominating the Universe at the end of inflation, dubbed as reheaton, the temperature of the radiation bath typically increases, reaching a maximum temperature...
I will present a novel framework for implementing stochastic inflation on stochastic trees, modelling the inflationary expansion as a branching process. The statistical properties of the curvature perturbation and other cosmological fields are encoded within the tree structure in a manner that fully captures quantum diffusion and its non-perturbative backreaction during inflation. Stochastic...
We discuss a mechanism of primordial black hole (PBH) formation that does not require specific features in the inflationary potential, revisiting previous literature. In this mechanism, a light spectator field evolves stochastically during inflation and remains subdominant during the post-inflationary era. Even though the curvature power spectrum stays small at all scales, rare perturbations...