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arXiv · 1212.4550

Statistical Naturalness and non-Gaussianity in a Finite Universe

Elliot Nelson·Sarah Shandera
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Abstract

We study the behavior of n-point functions of the primordial curvature perturbations, assuming our observed Universe is only a subset of a larger space with statistically homogeneous and isotropic perturbations. If the larger space has arbitrary n-point functions in a family of local type non-Gaussian statistics, sufficiently biased smaller volumes will have statistics from a `natural' version of that family with moments that are weakly non-Gaussian and ordered, regardless of the statistics of the original field. We also describe the effect of this bias on the shape of the bispectrum.

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Elliot Nelson, Sarah Shandera. 2012-12-19. Statistical Naturalness and non-Gaussianity in a Finite Universe. https://doi.org/10.1103/physrevlett.110.131301

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