Reissner-Nordstr\"om perturbation framework with gravitational wave applications

TL;DR

This paper introduces a new framework for modeling charged black hole perturbations and assesses how electric charge influences gravitational wave signals, especially relevant for upcoming LISA observations.

Contribution

The authors develop a streamlined perturbation framework for Reissner-Nordström black holes that improves upon previous methods and enables analysis of charged binary systems in gravitational wave astronomy.

Findings

Charge significantly affects gravitational waveforms, especially with opposite charge-to-mass ratios.

The framework allows precise calculation of electromagnetic and gravitational energy dissipation.

Results have implications for detecting charged black holes with LISA.

Abstract

We present a new convenient framework for modeling Reissner-Nordstr\"om black hole perturbations from charged distributions of matter. Using this framework, we quantify how gravitational wave observations of compact binary systems would be affected if one or both components were charged. Our approach streamlines the (linearized) Einstein-Maxwell equations through convenient master functions that we designed to ameliorate certain disadvantages of prior strategies. By solving our improved master equations with a point source, we are able to quantify the rate of orbital energy dissipation via electromagnetic and gravitational radiation. Through adiabatic and quasicircular approximations, we apply our dissipative calculations to determine trajectories for intermediate and extreme mass-ratio inspirals. By comparing trajectories and waveforms with varied charges to those with neutral components, we explore the potential effect of electric charge on gravitational wave signals. We observe that the case of opposite charge-to-mass ratios has the most dramatic impact. Our findings are largely interpreted through the lens of the upcoming LISA mission.