Particle motion in Horava-Lifshitz black hole space-times

TL;DR

This paper investigates particle trajectories around a Kehagias-Sfetsos black hole in Horava-Lifshitz gravity, revealing unique orbit types and discussing observable effects like light deflection and perihelion shift.

Contribution

It provides an exact numerical analysis of geodesics in a Horava-Lifshitz black hole spacetime, identifying new orbit types not seen in Schwarzschild solutions.

Findings

Massless and massive particles cannot reach the singularity at r=0.

Existence of manyworld bound and two-world escape orbits.

Discussion of observable effects such as perihelion shift and light deflection.

Abstract

We study the particle motion in the space-time of a Kehagias-Sfetsos (KS) black hole. This is a static spherically symmetric solution of a Horava-Lifshitz gravity model that reduces to General Relativity in the IR limit and deviates slightly from detailed balance. Taking the viewpoint that the model is essentially a (3+1)-dimensional modification of General Relativity we use the geodesic equation to determine the motion of massive and massless particles. We solve the geodesic equation exactly by using numerical techniques. We find that neither massless nor massive particles with non-vanishing angular momentum can reach the singularity at r=0. Next to bound and escape orbits that are also present in the Schwarzschild space-time we find that new types of orbits exist: manyworld bound orbits as well as two-world escape orbits. We also discuss observables such as the perihelion shift and the light deflection.