Whereas in the previous chapter we have derived the general solution of the homogeneous wave equation we now aim at solving the inhomogeneous wave equations for arbitrary sources \(\rho (\textbf{r};t)\) and \(\textbf{j}(\textbf{r};t)\) . To this aim we will use the method of Green’s functions that will lead to retarded potentials. The latter will be employed to calculate the electromagnetic radiation from moving point charges.