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arXiv · 2609.38990

RRR fluctuations from non-singular bounce

Sayantan Choudhury
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Abstract

We present a consistent treatment of regularization, renormalization, and resummation in a framework involving a contracting phase, a non-singular bounce, and inflation with a sharp transition from slow-roll to ultra-slow-roll, enabling primordial black hole production. Within an effective field theory approach, we compute quantum loop corrections to the power spectrum across all phases. Quadratic UV divergences are removed through renormalization, while logarithmic IR divergences are softened via resummation, demonstrating scheme independence. The inclusion of contraction and bounce allows the generation of solar-mass PBHs, $M_{\rm PBH}\sim{\cal O}(M_\odot)$, with minimal inflation $ΔN_{\rm Total}\sim{\cal O}(60)$, thereby evading the no-go theorem. For $0.88\le c_s\le1$, the peak spectrum amplitude lies within $10^{-3}\le A\le10^{-2}$, preserving causality and unitarity. PBH abundances across $10^{-33}\!-\!10^{-27}$ and $10^{-6}\!-\!10^{-1}M_\odot$ are confronted with microlensing constraints to control PBH overproduction.

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Sayantan Choudhury. 2026-09-30. RRR fluctuations from non-singular bounce. https://doi.org/10.1142/s0218271826410087

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