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arXiv · 2508.08238

Closing the Mass Window for Stupendously Large Black Holes

Christopher Gerlach·Yann Gouttenoire·Antonio J. Iovino·Nicholas Leister
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Abstract

We show that primordial black holes (PBHs) in the $\textit{Stupendously Large Black Hole}$ mass range ($M \gtrsim 10^{11}\,M_\odot$) produce isocurvature perturbations exceeding current $\textit{Planck}$ Cosmic Microwave Background limits, thereby excluding them as a significant dark matter component.

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Christopher Gerlach, Yann Gouttenoire, Antonio J. Iovino, Nicholas Leister. 2025-08-11. Closing the Mass Window for Stupendously Large Black Holes. https://arxiv.org/abs/2508.08238

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