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arXiv · 2306.17577

Supermassive primordial black holes in multiverse: for nano-Hertz gravitational wave and high-redshift JWST galaxies

Hai-Long Huang·Yong Cai·Jun-Qian Jiang·Jun Zhang·Yun-Song Piao
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Abstract

Recently, observational hints for supermassive black holes have been accumulating, which has inspired ones to wonder: Can primordial black holes (PBHs) be supermassive, in particular with the mass $M\gtrsim 10^{9}M_\odot$? A supercritical bubble (with an inflating baby universe inside it) that nucleated during inflation can develop into a PBH in our observable Universe. Here, we find that when the inflaton slowly passes by a neighboring vacuum, the nucleating rate of supercritical bubbles would inevitably attain a peak, so the mass distribution of multiverse PBHs, and the mass of peak can be up to $M\gtrsim 10^{11}M_\odot$. Thus our mechanism naturally provides a primordial origin of supermassive BHs.

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Hai-Long Huang, Yong Cai, Jun-Qian Jiang, Jun Zhang, Yun-Song Piao. 2023-06-30. Supermassive primordial black holes in multiverse: for nano-Hertz gravitational wave and high-redshift JWST galaxies. https://arxiv.org/abs/2306.17577

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