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Tests for primordial non-Gaussianity

Licia Verde·Raul Jimenez·Marc Kamionkowski·Sabino Matarrese
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Abstract

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as that which comes from topological defects. The tests we consider involve the cosmic microwave background (CMB), large-scale structure (LSS), high-redshift galaxies, and the abundances and properties of clusters. We find that the CMB is superior at finding non-Gaussianity in the primordial gravitational potential (as inflation would produce), while observations of high-redshift galaxies are much better suited to find non-Gaussianity that resembles that expected from topological defects. We derive a simple expression that relates the abundance of high-redshift objects in non-Gaussian models to the primordial skewness.

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Licia Verde, Raul Jimenez, Marc Kamionkowski, Sabino Matarrese. 2001-03-02. Tests for primordial non-Gaussianity. https://doi.org/10.1046/j.1365-8711.2001.04459.x

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