Work

Spectrum of third-order tensor perturbations induced by excited scalar fields

Year: 2025

Type: article

Abstract: We calculate for the first time the third-order spectrum of gravitational waves sourced by the scalar field perturbations amplified during inflation using the in-in formalism and discuss the conditions for the third-order spectrum to be smaller than the second-order one. We find that the third-order spectrum increases faster than the second-order one as the amplification of the field perturbations increases, and thus, the third-order spectrum dominates for detectable gravitational waves, which indicates that the perturbation theory breakdowns.

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

DOI: 10.1103/physrevd.111.103508

Authors: Cheng-Jun Fang, Zhi-Zhang Peng, Han-Wen Hu, Zong-Kuan Guo

Institutions: University of Chinese Academy of Sciences, Beijing Normal University

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Natural Science Foundation of China, National Key Research and Development Program of China

Awards: G3266504514, G3289481219, G4131717556