A canonical form for H-unitary matrices

Abstract

In this paper matrices A are considered that have the property that A∗HA = H ,where H = H∗ is invertible. A canonical form is given for the pair of matrices (A,H) under transformations (A,H) → ( S−1AS,S∗HS), where S is invertible, in which the canonical form for the A -matrix is the usual Jordan canonical form. The real case is studied as well