Dancing with black holes

TL;DR

This paper discusses the development and application of three regularization methods for direct N-body simulations of interacting black holes, including post-Newtonian effects, demonstrating their effectiveness in modeling black hole coalescence.

Contribution

It introduces and adapts three regularization techniques for large-N black hole simulations, incorporating post-Newtonian terms for realistic astrophysical scenarios.

Findings

Successful implementation of three regularization methods on large-N systems

Inclusion of post-Newtonian effects in black hole simulations

Simulations demonstrating black hole coalescence via gravitational radiation

Abstract

We describe efforts over the last six years to implement regularization methods suitable for studying one or more interacting black holes by direct N-body simulations. Three different methods have been adapted to large-N systems: (i) Time-Transformed Leapfrog, (ii) Wheel-Spoke, and (iii) Algorithmic Regularization. These methods have been tried out with some success on GRAPE-type computers. Special emphasis has also been devoted to including post-Newtonian terms, with application to moderately massive black holes in stellar clusters. Some examples of simulations leading to coalescence by gravitational radiation will be presented to illustrate the practical usefulness of such methods.