THEORETICAL AND EXPERIMENTAL METHODS FOR DETECTING THE CHARGE OF CHARGED BLACK HOLES

In the current paper we develop a set of theoretical and experimental methods for probing charged black holes. We calculate the trajectories of light in the vicinity of a charged black hole and we derive the Shapiro delay induced by a charged black hole. Based on the two experiments we infer the charge of the black hole, a process that has not been done previously. While by itself either test is not sufficient in order to determine the charge of a charged black hole, when combined, they become both necessary and sufficient in providing a full theoretical foundation for the experimental measurement of the charge of black holes. In the present paper we derive the closed form of the prediction for the charge of a charged black hole. By contrast, following the approach in [1,2,3], only a numerical approximation can be derived. This is important since closed solutions, though more difficult to derive, are easier to use and more elegant. What makes our method more elegant is the combination of the two experiments (the Shapiro delay and the light bending by the black hole).