Simple route to non-Gaussianity in inflation
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.
Keywords
Cite
@article{arxiv.astro-ph/0410486,
title = {Simple route to non-Gaussianity in inflation},
author = {G. I. Rigopoulos and E. P. S. Shellard and B. J. W. van Tent},
journal= {arXiv preprint arXiv:astro-ph/0410486},
year = {2009}
}
Comments
6 pages, 2 figures. v2: Updated formalism to version described in astro-ph/0504508, leading to dropping of one unnecessary approximation. Final results not significantly changed. Extended discussion of calculation and added graphical presentation of full momentum dependence. References corrected and added. v3: Final version, only small textual changes