QCD, Theoretical issues
Yu. L. Dokshitzer
TL;DR
The paper surveys QCD’s central challenges, focusing on the tension between perturbative quark-gluon dynamics and non-perturbative hadron phenomenology, with Gribov’s confinement ideas guiding the discussion. It analyzes small-x and BFKL dynamics, the role of confinement via the 'Heron' picture, and the impact of coherence and color transparency in high-energy scattering, including diffractive processes and J/psi production. A key thread is the interplay between perturbative predictions and infrared-sensitive non-perturbative effects, explored through ICS observables and the Wise Dispersive Method, which suggests universal power corrections tied to an infrared-finite coupling. The work also assesses QCD checks circa 1997, data preservation issues, and the need for proper theoretical tools and phenomenological frameworks to bridge soft and hard physics, outlining a path toward a unified understanding of confinement and hadron structure. Overall, the paper argues for integrating theory, phenomenology, and experiment to quantify non-perturbative contributions and advance QCD beyond its current puzzles.
Abstract
Today's QCD problems, prospects and achievements are reviewed.