Vincent Vennin (ICG, University of Portsmouth, United Kingdom)
In stochastic inflation, the quantum effects on the dynamics of the long wavelength perturbations are modelled by a stochastic noise. To study quantum corrections to inflationary observables, one thus needs to extract correlation functions of cosmological perturbations from this formalism. I will show how this can be done in practice, for all order correlation functions, in a non perturbative and fully analytical way. In the classical limit, when the potential is not too flat, quantum corrections are Planck suppressed and the standard results are recovered. In particular, this is the case for the modes within the CMB observable window. For some inflationary potentials however, quantum modifications can become large on smaller and/or larger scales, and we discuss the physical consequences of this effect.