Parametric resonance of gravitational waves in general scalar-tensor theories

authored by

Yi Fu Cai, Guillem Domènech, Alexander Ganz, Jie Jiang, Chunshan Lin, Bo Wang

Abstract

Gravitational waves offer a potent mean to test the underlying theory of gravity. In general theories of gravity, such as scalar-tensor theories, one expects modifications in the friction term and the sound speed in the gravitational wave equation. In that case, rapid oscillations in such coefficients, e.g. due to an oscillating scalar field, may lead to narrow parametric resonances in the gravitational wave strain. We perform a general analysis of such possibility within DHOST theories. We use disformal transformations to find the theory space with larger resonances, within an effective field theory approach. We then apply our formalism to a non-minimally coupled ultra-light dark matter scalar field, assuming the presence of a primordial gravitational wave background, e.g., from inflation. We find that the resonant peaks in the spectral density may be detectable by forthcoming detectors such as LISA, Taiji, Einstein Telescope and Cosmic Explorer.

Organisation(s)

Institute of Theoretical Physics
Faculty of Mathematics and Physics

External Organisation(s)

University of Science and Technology of China
Jagiellonian University
Pusan National University

Type

Article

Journal

Journal of Cosmology and Astroparticle Physics

Volume

2024

ISSN

1475-7516

Publication date

10.2024

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Astronomy and Astrophysics

Electronic version(s)

https://doi.org/10.48550/arXiv.2311.18546 (Access: Open)
https://doi.org/10.1088/1475-7516/2024/10/027 (Access: Open)