Meson-Meson Scattering in Relativistic Constraint Dynamics
  Dirac's relativistic constraint dynamics have been successfully applied to obtain a covariant nonperturbative description of QED and QCD bound states. We use this formalism to describe a microscopic theory of meson-meson scattering as a relativistic generalization of the nonrelativistic quark-interchange model developed by Barnes and Swanson. 
Horace W. Crater (UTSI) & Cheuk-Yin Wong (ORNL & UT)