Seminarium "Teoria cząstek elementarnych i kosmologia"

We discuss physics of inflationary cosmology beyond the assumption of standard slow-roll, and its consequences for metric perturbations leading to primordial black hole formation from large density fluctuations and first-order and second-order tensor perturbations propagating as gravitational waves. Next we will discuss how does the stochastic inflation offer a non-perturbative framework to calculate the distribution of density perturbations and in particular, large but rare fluctuations in the non-Gaussian tail of the distribution that could give rise to primordial black holes. We will discuss modelling of non-adiabatic perturbations on super-Hubble scales and we will compare the classical and stochastic delta-N formalisms used to calculate density perturbations.

Presentation based on arxiv.org/abs/2409.12950, arxiv.org/abs/2306.04002, and arxiv.org/abs/2407.15082.