On the inflationary interpretation of the nHz gravitational-wave background

Lorenzo Frosina; Alfredo Urbano

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arXiv · 2308.06915

On the inflationary interpretation of the nHz gravitational-wave background

Lorenzo Frosina·Alfredo Urbano

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Abstract

We construct a single-field model of inflation that achieves remarkable agreement with Planck and BICEP/Keck cosmological observations. The model, via the presence of an ultra-slow-roll phase, generates a sizable scalar-induced gravitational wave (GW) signal at nHz frequencies. We elucidate the distinctive features of this signal concerning its connection to the recent measurement of the low-frequency GW background reported by the NANOGrav collaboration.

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Lorenzo Frosina, Alfredo Urbano. 2023-08-14. On the inflationary interpretation of the nHz gravitational-wave background. https://arxiv.org/abs/2308.06915

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