PSEUDO-CANONICAL SYSTEMS WITH RATIONAL WEYL FUNCTIONS - EXPLICIT FORMULAS AND APPLICATIONS

The paper extends earlier results of the authors for canonical systems with spectral functions of which the absolutely continuous part has a rational derivative to a class of differential systems with skew self adjoint potentials. The corresponding direct and inverse spectral prob lems are solved explicitly, using state space methods from mathematica l system theory. Applications to nonlinear integrable partial differen tial equations are included. (C) 1998 Academic Press.