Divisibility and Riccati Equation
Harm Bart, Israel Gohberg, M. A. Kaashoek · Operator theory · 1979
Throughout this section X is a complex Banach space and π is a projection of X onto X 2 along X 1 . Matrix representations of operators acting on X will always be taken with respect to the decomposition X = X 1 ⊕ X 2 .