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arXiv · 2412.06764

How Well Do We Know the Scalar-Induced Gravitational Waves?

A. J. Iovino·S. Matarrese·G. Perna·A. Ricciardone·A. Riotto
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Abstract

Gravitational waves sourced by amplified scalar perturbations are a common prediction across a wide range of cosmological models. These scalar curvature fluctuations are inherently nonlinear and typically non-Gaussian. We argue that the effects of non-Gaussianity may not always be adequately captured by an expansion around a Gaussian field, expressed through nonlinear parameters such as $f_{\rm{NL}}$. As a consequence, the resulting amplitude of the stochastic gravitational wave background may differ significantly from predictions based on the standard quadratic source model routinely used in the literature.

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A. J. Iovino, S. Matarrese, G. Perna, A. Ricciardone, A. Riotto. 2024-12-09. How Well Do We Know the Scalar-Induced Gravitational Waves?. https://arxiv.org/abs/2412.06764

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