Publication date: Mar 2008
Abstract:
Properties of the Reissner-Nordstr"om black-hole and naked-singularity
spacetimes with a nonzero cosmological constant are represented by their
geodetical structure and embedding diagrams of the central planes of
both the ordinary geometry and associated optical reference geometry.
Motion of test particles and photons is described in terms of an
appropriate `effective potential.‘ Circular geodesics are discussed and
photon escape cones are determined. In all asymptotically anti-dS
black-hole spacetimes and some asymptotically dS black-hole spacetimes a
region containing stable circular geodesics exists, which allows
accretion processes in the disk regime. The inner region is limited from
below by particles with zero angular momentum that are located in stable
equilibrium positions. The inertial and gravitational forces related to
the optical reference geometry are introduced and specified for the
circular motion. It is shown how the properties of the centrifugal force
are closely related to the properties of the optical reference geometry
embedding diagrams.
Authors:
Stuchlík, Zdeněk; Hledík, Stanislav;