A consistent meson-exchange model for the NN interaction

The authors have constructed a meson-exchange model of the NN interaction which is solely based on suitable meson-nucleon and meson-nucleon-Δ-isobar vertices Wsub(α) (note that Δ-Δ transitions are not included). Antinucleons are left out from the beginning since it is known that the contribution of negative-energy states is quite small provided pseudo-vector coupling is used for the NNπ vertex, which is suggested as an effective coupling (Weinberg Lagrangian) starting from chiral invariance. The Hamiltonian H = H0 + W in time-ordered (non-covariant) perturbation theory. This treatment corresponds to standard many-body theory and thus leads to a well-defined transition from the two- to the many-body problem. (Auth.)