By requiring the linear differential operator in Newton's law of motion to be self adjoint, we obtain the field equation for the linear theory, which is the classical electrodynamics. In the process, we are also led to a fundamental universal chiral relation between electric and magnetic monopoles which implies that the two are related. Thus there could just exist only one kind of charge which is conventionally called electric.
Publication Source (Journal or Book title)
International Journal of Modern Physics A
Singh, P., & Dadhich, N. (2001). The field equation from Newton's law of motion and the absence of magnetic monopole. International Journal of Modern Physics A, 16 (7), 1237-1247. https://doi.org/10.1142/S0217751X01003147