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arXiv · 0808.4085

Signature of Primordial Non-Gaussianity on Matter Power Spectrum

Atsushi Taruya·Kazuya Koyama·Takahiko Matsubara
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Abstract

Employing the perturbative treatment of gravitational clustering, we discuss possible effects of primordial non-Gaussianity on the matter power spectrum. As gravitational clustering develops, the coupling between different Fourier modes of density perturbations becomes important and the primordial non-Gaussianity which intrinsically possesses a non-trivial mode-correlation can affect the late-time evolution of the power spectrum. We quantitatively estimate the non-Gaussian effect on power spectrum from the perturbation theory. The potential impact on the cosmological parameter estimation using the power spectrum are investigated based on the Fisher-matrix formalism. In addition, on the basis of the local biasing prescription, non-Gaussian effects on the galaxy power spectrum are considered, showing that the scale-dependent biasing arises from a local-type primordial non-Gaussianity. On the other hand, an equilateral-type non-Gaussianity does not induce such scale-dependence because of weaker mode-correlations between small and large Fourier modes.

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Atsushi Taruya, Kazuya Koyama, Takahiko Matsubara. 2008-12-25. Signature of Primordial Non-Gaussianity on Matter Power Spectrum. https://doi.org/10.1103/physrevd.78.123534

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