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arXiv · 1911.04359

Relativistic and non-Gaussianity contributions to the one-loop power spectrum

Rebeca Martinez-Carrillo·Josue De-Santiago·Juan Carlos Hidalgo·Karim A. Malik
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Abstract

We compute the one-loop density power spectrum including Newtonian and relativistic contributions, as well as the primordial non-Gaussianity contributions from $f_{\rm NL}$ and $g_{\rm NL}$ in the local configuration. To this end we take solutions to the Einstein equations in the long-wavelength approximation and provide expressions for the matter density perturbation at second and third order. These solutions have shown to be complementary to the usual Newtonian cosmological perturbations. We confirm a sub-dominant effect from pure relativistic terms, manifested at scales dominated by cosmic variance, but find that a sizable effect of order one comes from $g_{\rm NL}$ values allowed by Planck-2018 constraints, manifested at scales probed by forthcoming galaxy surveys like DESI and Euclid. As a complement, we present the matter bispectrum at the tree-level including the mentioned contributions.

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Rebeca Martinez-Carrillo, Josue De-Santiago, Juan Carlos Hidalgo, Karim A. Malik. 2020-04-13. Relativistic and non-Gaussianity contributions to the one-loop power spectrum. https://doi.org/10.1088/1475-7516%2F2020%2F04%2F028

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