Approximate Solutions of Predictive Relativistic Mechanics for the Electromagnetic Interaction. II

We solve the equations of predictive relativistic mechanics for the electromagnetic interaction of two structureless point charges, up to the first order in the mass ratio $\lambda \equiv \frac{m_1}{m_2}$, using as subsidiary conditions the Liénard-Wiechert formulas for both the advanced and retarded potentials. The perturbation technique used in this paper is, of course, only useful when $\lambda$ is a small number, but in this case it is more powerful than the technique used in a preceding paper by Bel, Salas, and Sánchez where the parameter used in the developments was the coupling constant.