Publication date: Oct 2018
Abstract:
The axial electromagnetic (EM) perturbations of the black hole (BH)
solutions in general relativity coupled to nonlinear electrodynamics
(NED) were studied for both electrically and magnetically charged BHs,
assuming that the EM perturbations do not alter the spacetime geometry
in our preceding paper [Phys. Rev. D 97, 084058 (2018),
10.1103/PhysRevD.97.084058]. Here, as a continuation of that work, the
formalism for the polar EM perturbations of the BHs in general
relativity coupled to the NED is presented. We show that the quasinormal
modes (QNMs) spectra of polar EM perturbations of the electrically and
magnetically charged BHs in the NED are not isospectral, contrary to the
case of the standard Reissner-Nordström BHs in the classical linear
electrodynamics. It is shown by the detailed study of QNMs properties in
the eikonal approximation that the EM perturbations can be a powerful
tool to confirm that in the NED light ray does not follow the null
geodesics of the spacetime. By specifying the NED model and comparing
axial and polar EM perturbations of the electrically and magnetically
charged BHs, it is shown that QNM spectra of the axial EM perturbations
of magnetically (electrically) charged BH and polar EM perturbations of
the electrically (magnetically) charged BH are isospectral, i.e.,
ωmagax≈ωelpol
(ωmagpol≈ωelax).
Authors:
Toshmatov, Bobir; Stuchlík, Zdeněk; Ahmedov, Bobomurat;