Canonical systems occupy a central position in the spectral theory of second order differential operators. They may be used to realize arbitrary spectral data, and the classical operators such as Schr├╢dinger, Jacobi, Dirac, and Sturm-Liouville equations can be written in this form. тАШSpectral Theory of Canonical SystemsтАЩ offers a selfcontained and detailed introduction to this theory. Techniques to construct self-adjoint realizations in suitable Hilbert spaces, a modern treatment of de Branges spaces, and direct and inverse spectral problems are discussed. Contents
Basic definitions
Symmetric and self-adjoint relations
Spectral representation
Transfer matrices and de Branges spaces
Inverse spectral theory
Some applications
The absolutely continuous spectrum
Canonical systems occupy a central position in the spectral theory of second order differential operators. They may be used to realize arbitrary spectral data, and the classical operators such as Schr├╢dinger, Jacobi, Dirac, and Sturm-Liouville equations can be written in this form. тАШSpectral Theo...