GENERALIZED COVARIANT 2-BODY WAVE-EQUATION

We show that the traditional quasipotential equations (QPEs) may be viewed as special cases of a more general QPE written in terms of three parameters. We analyze the behavior of the ladder QPEs for bound states in terms of these parameters. From the generalized QPE we obtain one QPE that resembles more closely to QED fourth order perturbative results than the traditional QPEs. We compare and contrast the QPEs in the low, intermediate, and large coupling regimes, including fits to heavy meson spectra.