Simple route to non-Gaussianity in inflation

G. I. Rigopoulos; E. P. S. Shellard; B. J. W. van Tent

doi:10.1103/physrevd.72.083507

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Simple route to non-Gaussianity in inflation

G. I. Rigopoulos·E. P. S. Shellard·B. J. W. van Tent

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Abstract

We present a simple way to calculate non-Gaussianity in inflation using fully non-linear equations on long wavelengths with stochastic sources to take into account the short-wavelength quantum fluctuations. Our formalism includes both scalar metric and matter perturbations, combining them into variables which are invariant under changes of time slicing in the long-wavelength limit. We illustrate this method with a perturbative calculation in the single-field slow-roll case. We also introduce a convenient choice of variables to graphically present the full momentum dependence of the three-point correlator.

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G. I. Rigopoulos, E. P. S. Shellard, B. J. W. van Tent. 2005-10-19. Simple route to non-Gaussianity in inflation. https://doi.org/10.1103/physrevd.72.083507

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