Pomeranchuk singularity and high-energy hadronic interactions

The Reggeon approach to high-energy hadronic interactions is reviewed and the dynamics of Regge poles in QCD is discussed with emphasis on the Pomeranchuk singularity in the complex angular momentum plane (pomeron). A possible link between the pomeron trajectory and the spectrum of glueballs is considered. High-energy hadronic interactions are described with the framework based on the Reggeon theory. It is shown that the concept of a pomeron is important not only for the theory of hadronic interactions but also for understanding high-energy heavy ion collisions and the small-x physics of deep inelastic scattering.