Exceptional Points, Nonnormal Matrices, Hierarchy of Spin Matrices and an Eigenvalue Problem
arXiv:1301.2900 · doi:10.1142/S0129183114500594
Abstract
Exceptional points of a class of non-hermitian Hamilton operators of the form are studied, where and are hermitian operators. Finite dimensional Hilbert spaces are considered. The linear operators and are given by spin matrices for spin . Since the linear operators studied are nonnormal, properties of such operators are described.
general improvements, references added, measure of nonnormality introduced