ELECTROMAGNETIC-FIELDS IN SCHWARZSCHILD AND REISSNER-NORDSTROM GEOMETRY - QUANTUM CORRECTIONS TO THE BLACK-HOLE ENTROPY

Using standard coordinates, the Maxwell equations in Reissner-Nordstro m geometry are written in terms of a couple of scalar fields satisfyin g Klein-Gordon-like equations. The density of states is derived in the semiclassical approximation and the first quantum correction to black hole entropy is computed by using the brick-wall model.