Quasinormal modes and strong cosmic censorship in near-extremal Kerr–Newman–de Sitter black-hole spacetimes

Shahar Hod

doi:10.1016/j.physletb.2018.03.020

Abstract

The quasinormal resonant modes of massless neutral fields in near-extremal Kerr–Newman–de Sitter black-hole spacetimes are calculated in the eikonal regime. It is explicitly proved that, in the angular momentum regime a¯>1−2Λ¯4+Λ¯/3, the black-hole spacetimes are characterized by slowly decaying resonant modes which are described by the compact formula ℑω(n)=κ+⋅(n+12) [here the physical parameters {a¯,κ+,Λ¯,n} are respectively the dimensionless angular momentum of the black hole, its characteristic surface gravity, the dimensionless cosmological constant of the spacetime, and the integer resonance parameter]. Our results support the validity of the Penrose strong cosmic censorship conjecture in these black-hole spacetimes.

Highlights

The dynamics of linearized matter and radiation fields in black-hole spacetimes are characterized by a discrete family of complex oscillation modes
The main goal of the present paper is to study analytically the quasinormal resonance spectra of massless neutral perturbation fields in non-asymptotically flat charged and rotating Kerr-Newman-de Sitter (KNdS) black-hole spacetimes
We shall explicitly prove below that, in the eikonal regime l ≫ 1, the quasinormal resonant modes of the near-extremal KNdS black-hole spacetimes with large enough angular momenta, a > aKc NdS(Λ), are characterized by the compact functional relation (2)

Summary

INTRODUCTION

The dynamics of linearized matter and radiation fields in black-hole spacetimes are characterized by a discrete family of complex (decaying in time) oscillation modes. Solving analytically the linearized Einstein-matter field equations, it has been explicitly proved that the fundamental (least damped) quasinormal resonant frequencies of equatorial massless perturbation modes of near-extremal Kerr black holes are characterized by the remarkably compact analytical relation [6,7,8,9,10]: Iω(n). We shall explicitly prove below that, in the eikonal (geometric-optics) regime l ≫ 1, the quasinormal resonant modes of the near-extremal KNdS black-hole spacetimes with large enough angular momenta, a > aKc NdS(Λ) (here Λ ≡ Λr+2 > 0 is the dimensionless cosmological constant of the black-hole spacetime), are characterized by the compact functional relation (2).

DESCRIPTION OF THE SYSTEM

SUMMARY