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On subscalarity of some \(2 \times 2\) \(M\)-hyponormal operator matrices. (English) Zbl 1472.47005

Summary: We provide some conditions for \(2 \times 2\) operator matrices whose diagonal entries are \(M\)-hyponormal operators to be subscalar. As a consequence, we obtain that a Weyl-type theorem holds for such operator matrices.

MSC:

47A08 Operator matrices
47B20 Subnormal operators, hyponormal operators, etc.
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