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arXiv · 1004.0818

Local non-Gaussianity from inflation

David Wands
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Abstract

The non-Gaussian distribution of primordial perturbations has the potential to reveal the physical processes at work in the very early Universe. Local models provide a well-defined class of non-Gaussian distributions that arise naturally from the non-linear evolution of density perturbations on super-Hubble scales starting from Gaussian field fluctuations during inflation. I describe the delta-N formalism used to calculate the primordial density perturbation on large scales and then review several models for the origin of local primordial non-Gaussianity, including the cuvaton, modulated reheating and ekpyrotic scenarios. I include an appendix with a table of sign conventions used in specific papers.

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David Wands. 2010-04-06. Local non-Gaussianity from inflation. https://doi.org/10.1088/0264-9381%2F27%2F12%2F124002

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