Publication date: Dec 2007
In the framework of the brany cosmology, the influence of the bulk spacetime on the black holes in the brane can be described by the so called tidal charge, which has a character similar to the charge parameter in the standard black-hole solutions, but can be both positive and negative. We discuss the influence of the tidal charge on the test particle and photon motion in the spherically symmetric spacetimes with a nonzero cosmological constant using the analysis realised in the case of Reissner-Nordström-(anti-)de Sitter spacetimes. We concentrate on the properties of circular geodesics as they play an important role in determining the brane properties of both thin and thick accretion discs. Some implications of the tidal charge influence are outlined.
Kološ, Martin; Stuchlík, Zdeněk; Hledík, Stanislav;