Further development of the new bound-state formalism

The new bound-state formalism developed previously is here extended in two important respects. First is the inclusion of self-energy effects and the demonstration of the implementability of the usual renormalization procedure by means of a calculation of the lowest-order self-energy effects comprising the Lamb shift in a hydrogenlike atom. Second is the derivation of the two-body equation for the particle-antiparticle case where annihilation effects enter. This is exemplified by the derivation of the positronium equation and a calculation of a (known) annihilation contribution to its singlet-triplet splitting. The entire development is facilitated by a modified functional formulation which chooses the fully interacting physical system as the unperturbed one. (AIP)