TY  - EJOUR
AU  - Konstandin, Thomas
AU  - Ballesteros, Guillermo
AU  - Egea, Jesús Gambín
AU  - Rodríguez, Alejandro Pérez
AU  - Pierre, Mathias
AU  - Rey Idler, Julian Leonardo
TI  - Intrinsic non-Gaussianity of ultra slow-roll inflation
IS  - DESY-24-205
M1  - PUBDB-2024-07866
M1  - DESY-24-205
M1  - arXiv:2412.14106
M1  - IFT UAM-CSIC 24-183
PY  - 2024
N1  - 28 pages, 7 figures; v2: added references + modified figure, results unaffected
AB  - We study the non-Gaussian tail of the curvature fluctuation, ζ, in an inflationary scenario with a transient ultra slow-roll phase that generates a localized large enhancement of the spectrum of ζ. To do so, we implement a numerical procedure that provides the probability distribution of ζ order by order in perturbation theory. The non-Gaussianities of ζ can be shown to arise from its non-linear relation to the inflaton fluctuations and from the intrinsic non-Gaussianities of the latter, which stem from its self interactions. We find that intrinsic non-Gaussianities, which have often been ignored to estimate the abundance of primordial black holes in this kind of scenario, are important. The relevance of the intrinsic contribution depends on the rapidity with which the transient ultra slow-roll phase occurs, as well as on its duration. Our method cannot be used accurately when the perturbative in-in formalism fails to apply, highlighting the relevance of developing fully non-perturbative approaches to the problem.
LB  - PUB:(DE-HGF)25
DO  - DOI:10.3204/PUBDB-2024-07866
UR  - https://bib-pubdb1.desy.de/record/619731
ER  -