Work

Ultraslow-roll inflation on the lattice: Backreaction and nonlinear effects

Year: 2025

Type: article

Abstract: Scenarios like $u\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}s\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}w\ensuremath{-}r\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}l$ Inflation significantly change the final stages of slow-roll inflation to create large curvature perturbations that produce gravitational waves (GW) and primordial black holes (PBH). These phases are outside the usual perturbative regime and the authors use lattice simulations to classify nonlinear effects and the backreaction on the background spacetime in ultraslow-roll Inflation. They show that the nonlinear effects introduce corrections around $20$%, which indicates that perturbation theory is not completely invalidated. However, the corrections are important to obtain correct PBH production rates and GW signals.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/physrevd.111.063518

Authors: Angelo Caravano, Gabriele Franciolini, Sébastien Renaux-Petel

Institutions: Institut d'Astrophysique de Paris, European Organization for Nuclear Research

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: European Commission, Sorbonne Université, Horizon 2020 Framework Programme, European Research Council

Awards: G2115634426, G434337789