Large fluctuations in the Sky

Abstract

Renormalization of quantum loop effects generated from large fluctuations is a hugely debatable topic of research these days which rules out the Primordial Black Hole (PBH) formation within the framework of single-field inflation. In this article, we briefly discuss that the correct implementation of regularization, renormalization, and resummation techniques in a setup described by an ultra-slow-roll phase sandwiched between two slow-roll phases in the presence of smooth or sharp transitions can lead to a stringent constraint on the PBH mass (i.e. $\mathcal{O}(10^2\mathrm{gm}$)), which we advertise as a new No-go theorem. Finally, we will give some of the possible way-outs using which one can evade this proposed No-go theorem and produce solar/sub-solar mass PBHs.

15 pages (10 pages material + 5 pages references), Essay written and received honorable mention for the Gravity Research Foundation 2024 Awards for Essays on Gravitation, Comments are welcome, Accepted for publication in Int. J. Mod. Phys. D (for the special issue on Gravity Research Foundation 2024 Awards for Essays on Gravitation)

References in corpus (4)

• The Effective Field Theory of Inflation
• Effective Field Theory for Inflation
• Single-field inflation, anomalous enhancement of superhorizon fluctuations, and non-Gaussianity in primordial black hole formation
• Primordial non-Gaussianity from ultra slow-roll Galileon inflation

Cited by in corpus (10)

• Primordial regular black holes as all the dark matter. II. Non-time-radial-symmetric and loop quantum gravity-inspired metrics
• Primordial regular black holes as all the dark matter. I. Time-radial-symmetric metrics
• Realisation of the ultra-slow roll phase in Galileon inflation and PBH overproduction
• Proving the absence of large one-loop corrections to the power spectrum of curvature perturbations in transient ultra-slow-roll inflation within the path-integral approach
• Obviating PBH overproduction for SIGWs generated by Pulsar Timing Arrays in loop corrected EFT of bounce
• Untangling PBH overproduction in $w$-SIGWs generated by Pulsar Timing Arrays for MST-EFT of single field inflation
• Mechanisms for producing Primordial Black Holes from Inflationary Models Beyond Fine-Tuning
• Primordial regular black holes as all the dark matter. III. Covariant canonical quantum gravity models
• Negative non-Gaussianity as a salvager for PBHs with PTAs in bounce
• Stochastic origin of primordial fluctuations in the Sky