Bounded Groups and Norm - Hermitian Matrices 9
نویسندگان
چکیده
and Hans Schneider· Department of Mathematics University of Wisconsin Madison, Wisconsin 53706 An elementary proof is given that a bounded multiplicative group of complex (real) n X n nonsingular matrices is similar to a unitary (orthogonal) group. Given a norm on a complex n-space, it follows that there exists a nonsingular n X n matrix L (the lAewner-John matrix for the norm) such that LHL -1 is Hermitian for every norm-Hermitian H. Numerous applications of this result are given.
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