Applicability of perturbative quantum chromodynamics to high-p/sub t/ exclusive scattering

Relations among high-p/sub t/ exclusive cross sections, particularly for γγ→baryon-antibaryon and for meson-nucleon scattering, test the applicability of perturbative QCD in the kinematic regime of the experiments. This permits assessment of the importance of higher-order corrections and non-leading-twist contributions to the Born approximation, the extent of the ''Sudakov suppression,'' and the validity of the asymptotic approximation to the wave functions