A charged black hole is a black hole that possesses electric charge. Since the electromagnetic repulsion in compressing an electrically charged mass is dramatically greater than the gravitational attraction (by about 40 orders of magnitude), it is not expected that black holes with a significant electric charge will be formed in nature.
Charged black holes are two of four possible types of black holes that have been found by solving Einstein's theory of gravitation, general relativity. The mathematical solutions for the shape of space and the electric and magnetic fields near a black hole are named after the persons who first worked them out. The solutions increase in complexity depending on which of the two parameters, J and Q, are zero (or not) (the mass M of a black hole could conceivably be tiny, but not zero). The four categories of solutions are given in the table below:
A mathematically-oriented article describes that the Reissner–Nordström metric for a charged, non-rotating black hole.[1] A similarly technical article on the Kerr–Newman black hole gives an overview of the most general known solution for a black hole, which has both angular momentum and charge (all the other solutions are simplified special cases of the Kerr–Newman black hole).
