A finite-size magnetic monopole in double-potential formalism

Using the double-potential formalism developed by Zwanziger, it is possible to construct nonsingular four-potentials corresponding to a given distribution of magnetic charge without violating the Bianchi identity. In this letter, we study a ball-like monopole with uniform distribution of magnetic charge. The corresponding four-potentials are found explicitly. We also construct the angular momentum operator of an electron in the field of such a monopole, which can be used to investigate the problem of electron-monopole scattering and to rectify Kazama-Yang-Goldhaber singularity.