Quantization of perturbations during inflation in the 1+3 covariant formalism

Abstract

This note derives the analogue of the Mukhanov-Sasaki variables both for scalar and tensor perturbations in the 1+3 covariant formalism. The possibility of generalizing them to non-flat Friedmann-Lemaitre universes is discussed.

4 pages: v2 has minor changes to match published version