A quantum field theoretic treatment of inclusive deep–inelastic diffractive scattering is given. The process can be described in the general framework of non–forward scattering processes using the light–cone expansion in the generalized Bjorken region. Evolution equations of the diffractive hadronic matrix elements are derived at the level of the twist– 2 contributions and are compared to those...

The study of the longitudinal polarization of Λ and Λ hyperons produced in polarized deep inelastic scattering, neutrino scattering, and in Z 0 decays allows one to access the spin dynamics of the quark fragmentation process. Different phenomenological spin transfer mechanisms are considered and predictions for the Λ and Λ longitudinal polarization in various processes using unpolarized and pol...

Experimental results obtained with the HERA collider and recent progress in their theoretical interpretation are reviewed. After a short introduction to HERA physics, deep inelastic scattering and photoproduction are discussed as (virtual) photon-proton scattering. It is shown that the measurement and theoretical understanding of both photoproduction as well as low-x deep inelastic scattering a...

I discuss several novel phenomenological features of QCD which are observable in deep inelastic lepton-nucleon and lepton-nucleus scattering. Initialand final-state interactions from gluon exchange, normally neglected in the parton model, have a profound effect on QCD hard-scattering reactions, leading to leading-twist single-spin asymmetries, the diffractive contribution to deep inelastic scat...

Recent measurements of the diffractive deep-inelastic cross section are used to extract diffrac-tive parton densities of the proton. These are subsequently applied in models to predict the production of jets and open charm in the final state. A rapidity gap suppression factor for dijet production in diffractive photoproduction relative to diffractive deep-inelastic scattering is obtained using ...