Stochastic inflation and non-perturbative power spectrum beyond slow roll

Autor:	Sharma, Devanshu
Rok vydání:	2024
Předmět:	Astrophysics - Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology
Druh dokumentu:	Working Paper
Popis:	Stochastic inflation, together with the $\Delta N$ formalism, provides a powerful tool for estimating the large-scale behaviour of primordial fluctuations. We construct a numerical code to capture the non-perturbative statistics of such fluctuations and test our code to obtain the exponential non-Gaussian tail of the curvature perturbations. We provide a numerical algorithm to compute the non-perturbative curvature power spectrum and apply it to slow-roll (SR) and ultra-slow-roll (USR) single-field models of inflation. For the USR case, we successfully reproduce the peak in the power spectrum, which agrees to a certain accuracy with the perturbative power spectrum. We highlight some important differences between non-perturbative and perturbative approaches that may suggest the inconsistency of the $\Delta N$ formalism at the transition stages between attractor and non-attractor regimes. Comment: 25 pages, 9 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2411.08854 Zobrazit plný text záznamu View this record from Arxiv