Orbital resonances around Black holes

TL;DR

This paper calculates the properties of resonant orbits around Kerr black holes, highlighting their potential observability through gravitational waves, black hole imaging, and accretion disk oscillations, and discusses implications for detecting deviations from Kerr geometry.

Contribution

It provides a comprehensive analysis of resonant orbit characteristics across all parameters in Kerr spacetime, including potential observational signatures and implications for non-Kerr spacetimes.

Findings

Resonance effects could be observed with current and future detectors.

Resonance locations are key to understanding geodesic chaos.

Quantitative resonance data for all Kerr parameters are provided.

Abstract

We compute the length and timescales associated with resonant orbits in the Kerr Metric for all orbital and spin parameters. Resonance induced effects are potentially observable when the Event Horizon telescope resolves the inner structure of Sgr A*, space-based gravitational wave detectors record phase-shifts in the waveform during the resonant passage of a neutron star as it spirals in to the black hole and in the frequencies of quasi periodic oscillations for accreting black holes. The onset of geodesic chaos for non-Kerr spacetimes should occur at the resonance locations quantified here.