Commutable Matrix-Valued Functions and Operator-Valued Functions
Commutable Matrix-Valued Functions and Operator-Valued Functions
A simple expression is established for an analytic commutable matrix-valued function. Then a characterization of two by two functional commutative matrices is proven. Finally, a family of analytic normal compact operators on a Hilbert space, which commute with their derivatives, is shown to be functionally commutative.
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