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arXiv · 1104.0292

Gauge invariance and non-Gaussianity in Inflation

Gerasimos Rigopoulos
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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 $t={\rm const}$ hypersurfaces and the use of boundary terms in computations of non-Gaussianity.

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Gerasimos Rigopoulos. 2011-07-19. Gauge invariance and non-Gaussianity in Inflation. https://doi.org/10.1103/physrevd.84.021301

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