Black-Hole Scattering in Einstein-scalar-Gauss-Bonnet: Numerical Relativity Meets Analytics

TL;DR

This paper compares numerical simulations and analytical models of black hole scattering in Einstein-scalar-Gauss-Bonnet gravity, demonstrating strong agreement and advancing semi-analytical waveform development for modified gravity theories.

Contribution

It provides the first fully nonlinear numerical simulations of black hole scattering in Einstein-scalar-Gauss-Bonnet gravity and validates an effective-one-body analytical approach.

Findings

Excellent agreement between numerical and analytical scattering angles.

Accurate modeling of strong-field scalar-gravitational dynamics.

Progress towards semi-analytical waveforms in modified gravity.

Abstract

The study of hyperbolic binary black hole encounters yields an effective probe of the strong field regime of black holes, thus providing an additional channel to test General Relativity. We study the scattering of two black holes in Einstein-scalar-Gauss-Bonnet gravity, a well-motivated effective field theory of gravity, by comparing the scattering angle obtained from the first fully nonlinear black hole scattering simulations with its effective-one-body analytic description. We obtain excellent agreement between analytics and numerics, exhibiting accurate capturing of strong-field scalar-gravitational dynamics. Our work paves the way towards semi-analytical waveform templates of compact object binaries in modified theories of gravity.