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arXiv · 1906.08697

Time-sliced perturbation theory with primordial non-Gaussianity and effects of large bulk flows on inflationary oscillating features

Anagha Vasudevan·Mikhail M. Ivanov·Sergey Sibiryakov·Julien Lesgourgues
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Abstract

We extend the formalism of time-sliced perturbation theory (TSPT) for cosmological large-scale structure to include non-Gaussian initial conditions. We show that in such a case the TSPT interaction vertices acquire new contributions whose time-dependence factorizes for the Einstein-de Sitter cosmology. The new formulation is free from spurious infrared (IR) enhancements and reveals a clear IR structure of non-Gaussian vertices. We use the new technique to study the evolution of oscillating features in primordial statistics and show that they are damped due to non-linear effects of large bulk flows. We derive the damping factors for the oscillating primordial power spectrum and bispectrum by means of a systematic IR resummation of relevant Feynman diagrams.

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Anagha Vasudevan, Mikhail M. Ivanov, Sergey Sibiryakov, Julien Lesgourgues. 2019-06-20. Time-sliced perturbation theory with primordial non-Gaussianity and effects of large bulk flows on inflationary oscillating features. https://doi.org/10.1088/1475-7516%2F2019%2F09%2F037

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