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arXiv · 1111.2721

Inhomogeneous non-Gaussianity

Christian T. Byrnes·Sami Nurmi·Gianmassimo Tasinato·David Wands
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Abstract

We propose a method to probe higher-order correlators of the primordial density field through the inhomogeneity of local non-Gaussian parameters, such as f_NL, measured within smaller patches of the sky. Correlators between n-point functions measured in one patch of the sky and k-point functions measured in another patch depend upon the (n+k)-point functions over the entire sky. The inhomogeneity of non-Gaussian parameters may be a feasible way to detect or constrain higher-order correlators in local models of non-Gaussianity, as well as to distinguish between single and multiple-source scenarios for generating the primordial density perturbation, and more generally to probe the details of inflationary physics.

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Christian T. Byrnes, Sami Nurmi, Gianmassimo Tasinato, David Wands. 2012-09-27. Inhomogeneous non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2012%2F03%2F012

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