Merging black holes with Cauchy-characteristic matching: Computation of late-time tails

TL;DR

This paper demonstrates that Cauchy-characteristic matching (CCM) can effectively simulate binary black hole mergers and accurately compute late-time gravitational wave tails, advancing numerical relativity techniques.

Contribution

The authors successfully perform nine CCM simulations of binary black holes, showing CCM's robustness for fully nonlinear dynamical spacetimes and its application to late-time tail computation.

Findings

Nine successful CCM binary black hole simulations

Accurate computation of late-time gravitational wave tails

Potential for systematic studies and improved waveform modeling

Abstract

Cauchy-characteristic matching (CCM) is a numerical-relativity technique that solves Einstein's equations on an effectively infinite computational domain, thereby eliminating systematic errors associated with artificial boundary conditions. Whether CCM can robustly handle fully nonlinear, dynamical spacetimes, such as binary black hole (BBH) mergers, has remained an open question. In this work, we provide a positive answer by presenting nine successful CCM simulations of BBHs; and demonstrate a key application of this method: computing late-time tails. Our results pave the path for systematic studies of late-time tails in BBH systems, and for producing highly accurate waveforms essential to next-generation gravitational-wave detectors.