Representation of contractive solutions of a class of algebraic Riccati equations as characteristic functions of maximal dissipative operators (Q2642726)

The author investigates a particular class of parametrized algebraic Riccati equations, where the parameter belongs to the open right half-plane. As a generalization of standard results on Riccati equations and using techniques from operator theory, it is shown that a unique stabilizing (contractive) solution exists under a positivity condition on the matrix coefficients. This solution can be interpreted as the characteristic function of a dissipative operator generated by a periodic Hamiltonian differential equation.