Asymptotic chiral invariance. II. The consequences

Based upon the invariance of SU(2)⊗SU(2) and SU(3)⊗SU(3) for asymptotic momenta, we first derive constraints on certain strong and electromagnetic exclusive scattering processes, where all the hadrons are viewed as fundamental fields. Then we consider asymptotic SU(3)⊗SU(3) for meson-meson and baryon-baryon fixed-angle, elastic scattering in the Landshoff model, wherein the hadrons are viewed as bound states of quarks and antiquarks. We find that the part of the pseudoscalar-pseudoscalar scattering amplitude which is a function of the center-of-mass scattering angle only is just the average of the analogous functions of the scattering angle for the independent nonzero helicity amplitudes for vector-vector scattering. Finally, in the case of baryon-baryon scattering we find that total baryon helicity is conserved.