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Criteria of unitary equivalence of Hermitian operators with a degenerate spectrum. (English) Zbl 0849.15006

Nonimprovable estimates of the number of necessary and sufficient conditions for two Hermitian operators to be unitarily equivalent in a unitary space are obtained when the multiplicities of eigenvalues of operators can be more than 1. The explicit form of these conditions is given. Following a set of theorems, two examples are given.
Reviewer: Y.Kuo (Knoxville)

MSC:

15A21 Canonical forms, reductions, classification
15A18 Eigenvalues, singular values, and eigenvectors
15B57 Hermitian, skew-Hermitian, and related matrices
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References:

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