Regular and chaotic motion in general relativity: The case of an inclined black hole magnetosphere

TL;DR

This paper investigates how the inclination of an external magnetic field affects the regularity or chaos in charged particle motion near a rotating black hole, using numerical methods and chaos quantification techniques.

Contribution

It introduces a non-axisymmetric model with an inclined magnetic field and analyzes its impact on particle dynamics near black holes, highlighting the role of initial conditions.

Findings

Inclined magnetic fields can induce chaotic particle trajectories.

Initial azimuthal angle significantly influences the motion regime.

Maximal Lyapunov exponents and Recurrence Quantification Analysis effectively characterize chaos.

Abstract

Dynamics of charged particles in the vicinity of a rotating black hole embedded in the external large-scale magnetic field is numerically investigated. In particular, we consider a non-axisymmetric model in which the asymptotically uniform magnetic field is inclined with respect to the axis of rotation. We study the effect of inclination onto the prevailing dynamic regime of particle motion, i.e. we ask whether the inclined field allows regular trajectories or if instead, the deterministic chaos dominates the motion. In this contribution we further discuss the role of initial condition, particularly, the initial azimuthal angle. To characterize the measure of chaoticness we compute maximal Lyapunov exponents and employ the method of Recurrence Quantification Analysis.