Measuring scalar charge with compact binaries: High accuracy modeling with self-force

Spiers, Andrew; Maselli, Andrea; Sotiriou, Thomas P.

Abstract

Using the self-force approach, we present the premier first-post-adiabatic accuracy formalism for modeling compact binaries in theories with a massless scalar field nonminimally coupled to gravity. We limit the binary secondary to being a non-spinning compact body with no scalar dipole (we will address the spinning and scalar dipole cases in an upcoming paper). By producing an ansatz for the scalar charged point particle action, we derive first- and second-order perturbative field equations and equations of motion for the secondary compact object. Under our assumptions, implementing this formalism will produce sufficiently accurate waveform templates for precision measurements of the scalar charge of the secondary with LISA data on extreme-mass-ratio inspirals. Our formalism is consistent with almost general scalar-tensor theories of gravity. Implementing our formalism builds on self-force models in general relativity; we show the incorporation into the two-timescale formalism is straightforward. Excitingly, implementation poses no significantly more challenging barriers than computing first-post-adiabatic waveforms in general relativity.

Citation

Spiers, A., Maselli, A., & Sotiriou, T. P. (2024). Measuring scalar charge with compact binaries: High accuracy modeling with self-force. Physical Review D, 109(6), Article 064022. https://doi.org/10.1103/physrevd.109.064022

• Journal Article Type: Article
• Acceptance Date: Jan 29, 2024
• Online Publication Date: Mar 8, 2024
• Publication Date: Mar 15, 2024
• Deposit Date: Mar 18, 2024
• Publicly Available Date: Mar 18, 2024
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 109
• Issue: 6
• Article Number: 064022
• DOI: https://doi.org/10.1103/physrevd.109.064022
• Keywords: Alternative gravity theories; Gravitation; Gravitational waves
• Public URL: https://nottingham-repository.worktribe.com/output/32471205
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.109.064022