A quantum mechanical theory of the action-at-a-distance electrodynamics of Wheeler and Feynman is given using an S-matrix approach. The response of the universe is introduced, and a perturbation expansion leads to the usual expression for the spontaneous transition rate between atomic energy levels, an effect normally attributed to quantized field oscillators. The Feynman propagator is then recovered, leading to the familiar self-energy formulae. Finally, a comparison of the formal structure of the new theory with the conventional is shown to establish a complete mathematical equivalence to all orders in the expansion.

Analytical reflexion coefficients are obtained for horizontally and vertically polarized electromagnetic waves respectively, obliquely incident from below two recently devised models of horizontally stratified isotropic media. It is shown that both models are totally reflecting and the phases of the reflexion coefficients may be expressed in terms of arg Γ(z).