Work

Conservation of superhorizon curvature perturbations at one loop: Backreaction in the in-in formalism and renormalization

Year: 2025

Type: article

Abstract: We show that the superhorizon-limit curvature perturbations are conserved at one-loop level in single-field inflation models with a transient nonslow-roll period. We take the spatially flat gauge, where the backreaction plays a crucial role for the conservation of superhorizon curvature perturbations unless the counterterms are tuned. We calculate the backreaction with the in-in formalism. In addition, we explicitly show the renormalization of the UV divergences with the counterterms.

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

DOI: 10.1103/physrevd.111.103504

Author: Keisuke Inomata

Institution: Johns Hopkins University

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funder: Japan Society for the Promotion of Science

OpenAlex ID: W4410088438

FWCI: 6.327

Cites: 75

Cited by: 14

Related to: 10