Meson-Baryon Scattering in the Quark Model

We obtain many sum rules for meson-baryon scattering amplitudes considering the quark-quark and the quark-antiquark amplitudes, for the appropriate meson and baryon states. The main differences from earlier work are that mesons are consistently treated as quark-antiquark pairs and not as elementary fields, and that the usual symmetry representation of the states has been taken into account. Further, the assumption that the real part of the amplitude is dominated by quark-quark forces and the imaginary part by quark-antiquark forces yields sum rules connecting these real and imaginary parts for different processes, in consonance with duality requirements.