Publication date: Jul 2005
Abstract:
Relativistic Keplerian orbital frequency (νK) and related
epicyclic frequencies (radial νr, vertical νθ)
play an important role in the physics of accretion discs orbiting Kerr
black holes – quasiperiodic oscillations observed in microquasars can be
explained by associated resonant or trapping effects. Because of growing
theoretical evidence of the possible existence of naked singularities,
we discuss the behaviour of the fundamenal orbital frequencies for
Keplerian motion in the field of Kerr naked singularities, primarily in
order to find phenomena that could observationally distinguish a
hypothetical naked singularity from black holes. Some astrophysically
important consequences are sketched, namely the existence of strong
resonant frequency for all Kerr naked singularities, with radial and
vertical epicyclic frequencies equal and given by the relation ω_sr =
a-2√{a^2-1} (a^2+1 )-1.
Authors:
Török, G.; Stuchlík, Z.;