| Citation | Distinguished for his work on the analytic properties of scattering amplitudes, fundamental to the use of relativistic quantum mechanics in subnuclear refraction theory. He has contributed substantially to the study of the singularities of Feynman integrals, giving an early demonstration of the existence of Regge poles in relativistic quantum mechanics and making a series of important contributions to the theory of Regge cuts. He has also made many contributions to S-matrix theory, including the first derivation of the Landau equations in that context and a complete analysis of physical region singularity structure.
In the last three years his work has been concerned with the construction of general covariant models corresponding to the parton picture of hadronic structure, together with the development of a quantitative theory based on more detailed dynamical assumptions. This has resulted in a model giving good agreement with experiment in the recent extremely important fields of deep inelastic lepton scattering and of hadronic processes at large transverse momentum. |