Correspondence of eikonal quasinormal modes and unstable fundamental photon orbits for Kerr-Newman black hole

In this work, we study the relation of the eikonal quasinormal modes (EQNMs) and the unstable fundamental photon orbits (UFPOs) in the Kerr-Newman spacetime. We find that in the eikonal limit the gravitational and electromagnetic perturbations of the Kerr-Newman black hole are naturally decoupled, a...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2021-09
Main Authors: Peng-Cheng, Li, Tsai-Chen, Lee, Guo, Minyong, Chen, Bin
Format: Article
Language:English
Subjects:
Boundary conditions
Klein-Gordon equation
Liapunov exponents
Perturbation
Relativity
Scalars
Spacetime
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this work, we study the relation of the eikonal quasinormal modes (EQNMs) and the unstable fundamental photon orbits (UFPOs) in the Kerr-Newman spacetime. We find that in the eikonal limit the gravitational and electromagnetic perturbations of the Kerr-Newman black hole are naturally decoupled, and a single one-dimensional Schr\"odinger-like equation encoding the QNM spectrum can be derived. We then show that the decoupled Teukolsky master equation and the Klein-Gordon equation for the massless scalar field in the Kerr-Newman spacetime are of the same form in the eikonal limit. As a direct consequence, taking into account of the boundary conditions for EQNMs we show an exact correspondence between EQNMs and UFPOs, that is, EQNM/UFPO correspondence. More precisely, similar to the Kerr case, the real part of EQNM's frequency is a linear combination of the precessional and (polar) orbital frequencies, while the imaginary part of the frequency is proportional to the Lyapunov exponent of the UFPO.
ISSN:2331-8422
DOI:10.48550/arxiv.2105.14268