Gravitational Waves from Spinning Compact Binaries

TL;DR

This paper confirms that the dynamics of spinning compact binaries in general relativity are chaotic at the second post-Newtonian level, with dissipation dampening chaos but leaving observable imprints during the inspiral-to-plunge transition.

Contribution

It clarifies the chaotic nature of spinning compact binary dynamics within the second post-Newtonian approximation, resolving previous contradictory claims.

Findings

Binary systems exhibit chaos in their dynamics.

Dissipation reduces but does not eliminate chaos.

Chaotic signatures persist during the inspiral-to-plunge transition.

Abstract

Binary systems of rapidly spinning compact objects, such as black holes or neutron stars, are prime targets for gravitational wave astronomers. The dynamics of these systems can be very complicated due to spin-orbit and spin-spin couplings. Contradictory results have been presented as to the nature of the dynamics. Here we confirm that the dynamics - as described by the second post-Newtonian approximation to general relativity - is chaotic, despite claims to the contrary. When dissipation due to higher order radiation reaction terms are included, the chaos is dampened. However, the inspiral-to-plunge transition that occurs toward the end of the orbital evolution does retain an imprint of the chaotic behaviour.