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arXiv · 1112.3895

Constructing Regularized Cosmic Propagators

Francis Bernardeau·Martin Crocce·Roman Scoccimarro
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Abstract

We present a new scheme for the general computation of cosmic propagators that allow to interpolate between standard perturbative results at low-k and their expected large-k resummed behavior. This scheme is applicable to any multi-point propagator and allows the matching of perturbative low-k calculations to any number of loops to their large-k behavior, and can potentially be applied in case of non-standard cosmological scenarios such as those with non-Gaussian initial conditions. The validity of our proposal is checked against previous prescriptions and measurements in numerical simulations showing a remarkably good agreement. Such a generic prescription for multi-point propagators provides the necessary building blocks for the computation of polyspectra in the context of the so-called Gamma-expansion introduced by Bernardeau et al. (2008). As a concrete application we present a consistent calculation of the matter bispectrum at one-loop order.

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Francis Bernardeau, Martin Crocce, Roman Scoccimarro. 2012-05-22. Constructing Regularized Cosmic Propagators. https://doi.org/10.1103/physrevd.85.123519

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