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arXiv · 2308.14688

Exploring the NANOGrav Signal and Planet-mass Primordial Black Holes through Higgs Inflation

Zhu Yi·Zhi-Qiang You·You Wu·Zu-Cheng Chen·Lang Liu
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Abstract

The data recently released by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) provides compelling evidence supporting the existence of a stochastic signal that aligns with a gravitational-wave background. We show that the scalar-induced gravitational waves from the Higgs inflation model with the parametric amplification mechanism can explain this signal. Such a gravitational-wave background naturally predicts the substantial existence of planet-mass primordial black holes, which can be planet 9 in our solar system and the lensing objects for the ultrashort-timescale microlensing events observed by the Optical Gravitational Lensing Experiment. Therefore, the NANOGrav signal, the potential Planet 9 in our solar system, and the Optical Gravitational Lensing Experiment can be explained within the framework of Higgs inflation.

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Zhu Yi, Zhi-Qiang You, You Wu, Zu-Cheng Chen, Lang Liu. 2023-08-28. Exploring the NANOGrav Signal and Planet-mass Primordial Black Holes through Higgs Inflation. https://doi.org/10.1088/1475-7516%2F2024%2F06%2F043

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