Primordial Black Holes and Loops in Single-Field Inflation

Hassan Firouzjahi; Antonio Riotto

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arXiv · 2304.07801

Primordial Black Holes and Loops in Single-Field Inflation

Hassan Firouzjahi·Antonio Riotto

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Abstract

Using the $\delta N$ formalism we calculate the one-loop correction to the large-scale power spectrum of the curvature perturbation in the standard scenario where primordial black holes are formed in the early universe thanks to a phase of ultra-slow-roll in single-field inflation. We explicitly show that one-loop corrections are negligible when the transition from the ultra-slow-roll to the slow-roll phase is smooth. We conclude that the PBH formation scenario through a ultra-slow-roll phase is viable.

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Hassan Firouzjahi, Antonio Riotto. 2023-04-16. Primordial Black Holes and Loops in Single-Field Inflation. https://arxiv.org/abs/2304.07801

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