Stochastic Inflation and Primordial Black Holes

In the inflationary paradigm, the transition from quantum fluctuations to classical but stochastic density perturbations plays an important role. In particular, it implies that the open quantum system comprising the super-Hubble degrees of freedom can be described with a classical stochastic theory, the “stochastic inflation” formalism. In this framework, the short-wavelength quantum fluctuations act as a classical noise on the dynamics of the super-Hubble scales.

I will explain which quantum backreaction signatures are left by this effect on the correlation functions of primordial cosmological perturbations. I will discuss the conditions under which these can be large even at sub-Planckian energy, and I will explain which prospects it opens for probing quantum gravity effects on inflationary dynamics. As an application, I will show how the formation of primordial black holes formation from inflation is dominated by these stochastic effects.

Dates: 

Mardi, 19 septembre, 2017 - 14:00

Salle / Local: 

483 A - Malevitch

Nom/Prénom // Last name/First name: 

Vincent Vennin

Affiliation: 

APC

Equipe organisatrice / Organizing team: 

  • Théorie