Recent developments in obtaining a detailed model for gamma ray bursts have
shown the need for a deeper understanding of phenomena described by solutions
of the Einstein-Maxwell equations, reviving interest in the behavior of charges
close to a black hole. In particular a drastic difference has been found
between the lines of force of a charged test particle in the fields of
Schwarzschild and Reissner-Nordstrom black holes. This difference characterizes
a general relativistic effect for the electric field of a charged test particle
around a (charged) Reissner-Nordstrom black hole similar to the "Meissner
effect" for a magnetic field around a superconductor. These new results are
related to earlier work by Fermi and Hanni-Ruffini-Wheeler.Comment: 25 pages, 17 figures, to appear on the Proceedings of "Analysis,
manifolds and geometric structures in physics", International Conference in
Honour of Y. Choquet-Bruhat, Isola d'Elba June 24th-26th, 200
