Geodesics and Geodesic Deviation in static Charged Black Holes

Abstract

The radial motion along null geodesics in static charged black hole space-times, in particular, the Reissner-Nordstr\"om and stringy charged black holes are studied. We analyzed the properties of the effective potential. The circular photon orbits in these space-times are investigated. We found that the radius of circular photon orbits in both charged black holes are different and differ from that given in Schwarzschild space-time. We studied the physical effects of the gravitational field between two test particles in stringy charged black hole and compared the results with that given in Schwarzschild and Reissner-Nordstr\"om black holes.