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arXiv · 2105.01659

Non-Gaussianity and the induced gravitational wave background

Peter Adshead·Kaloian D. Lozanov·Zachary J. Weiner
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Abstract

Scalar metric fluctuations generically source a spectrum of gravitational waves at second order in perturbation theory, poising gravitational wave experiments as potentially powerful probes of the small-scale curvature power spectrum. We perform a detailed study of the imprint of primordial non-Gaussianity on these induced gravitational waves, emphasizing the role of both the disconnected and connected components of the primoridal trispectrum. Specializing to local-type non-Gaussianity, we numerically compute all contributions and present results for a variety of enhanced primordial curvature power spectra.

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Peter Adshead, Kaloian D. Lozanov, Zachary J. Weiner. 2021-05-04. Non-Gaussianity and the induced gravitational wave background. https://doi.org/10.1088/1475-7516%2F2021%2F10%2F080

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