Gauge invariance and non-Gaussianity in Inflation

Abstract

We clarify the role of gauge invariance for the computation of quantum non-Gaussian correlators in inflation. A gauge invariant generating functional for n-point functions is given and the special status of the spatially flat gauge is pointed out. We also comment on the relation between gauge transformations, field redefinitions, the choice of $t=\mathrm{const}$ hypersurfaces and the use of boundary terms in computations of non-Gaussianity.

4 pages, no figures; v2: 5 pages, no figures, substantial text added, results unchanged, published in PRD Rapid Communications

References in corpus (1)

• A note on the role of the boundary terms for the non-Gaussianity in general k-inflation