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arXiv · 1211.3086

A Modal Approach to the Numerical Calculation of Primordial non-Gaussianities

Hiroyuki Funakoshi·Sébastien Renaux-Petel
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Abstract

We propose a new method to numerically calculate higher-order correlation functions of primordial fluctuations generated from any early-universe scenario. Our key-starting point is the realization that the tree-level In-In formalism is intrinsically separable. This enables us to use modal techniques to efficiently calculate and represent non-Gaussian shapes in a separable form well suited to data analysis. We prove the feasibility and the accuracy of our method by applying it to simple single-field inflationary models in which analytical results are available, and we perform non-trivial consistency checks like the verification of the single field consistency relation. We also point out that the i epsilon prescription is automatically taken into account in our method, preventing the need for ad-hoc tricks to implement it numerically.

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Hiroyuki Funakoshi, Sébastien Renaux-Petel. 2012-11-13. A Modal Approach to the Numerical Calculation of Primordial non-Gaussianities. https://doi.org/10.1088/1475-7516%2F2013%2F02%2F002

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