Problems of Modern Quantum Field Theory

This volume is the compilation of invited lectures presented at the Spring School "Problems of Modern Quantum Field Theory" held in Alushta (USSR) April 24-May 5 1989, organized by the Institute for Theoretical Physics (Kiev) and Landau Institute for Theoretical Physics (Moscow). Approximately one hundred physicists and mathematicians attended lectures on aspects of mod ern quantum field theory: Conformal Field Theory, Geometrical Quantization, Quantum Groups and Knizhnik-Zamolodchikov Equations, Non-Archimedian Strings, Calculations on Riemannian Surfaces. A number of experts active in research in these areas were present and they shared their ideas in both formal lectures and informal conversations. V. Drinfeld discusses the relation between quasi-Hopf algebras, conformal field theory, and knot invariants. The author sketches a new proof of Konno's theorem on the equivalence of the braid group representations corresponding to R-matrices and the Knizhnik-Zamolodchikov equation. The main ideas of quantum analogs of simple Lie superalgebras and their dual objects - algebras of functions on the quantum supergroup - are introduced in the paper by P.P. Kulish. He proposes the universal R-matrix for simplest superalgebra osp(2/1) and discusses the elements of a representation theory. In the paper by A. Alekseev and S. Shatashvili the correspondence between geometrical quantization and conformal field theory is established. It allows one to develop a Lagrange approach to two-dimensional conformal field theory. The authors also discuss the relation to finite R-matrices.