# spring workshop on gravity and cosmology

May 16 – 17, 2019
University of Warsaw
Europe/Zurich timezone

## Stochastic inflation beyond slow roll

May 16, 2019, 2:30 PM
45m
O.06 (faculty of physics)

### O.06

#### faculty of physics

university of warsaw

### Speaker

David Wands (ICG)

### Description

I will discuss how to apply stochastic formalism for inflation beyond the usual slow-roll approximation. We verify that the assumptions on which the stochastic formalism relies still hold even far from the slow-roll attractor. In particular this requires the separate universe assumption to hold for long-wavelength perturbations of the scalar field beyond slow roll. In general, there is a gauge correction to the amplitude of the stochastic noise which is usually calculated in the spatially-flat gauge. We show that if the number of e-folds is used as the time variable (the uniform-N gauge) then these corrections vanish in the slow-roll limit, but we explain how to calculate them in general.