Natural Science, Mathematics, 2025
On Characteristic Function of a Contraction, Its Model and Function of Strauss
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Submitted: 2024-12-17; Published: 2024-12-17
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Abstract
It is shown that Nagy-Foias characteristic function of a completely nonunitary contraction and a variant of its functional model can be presented by means of projection-valued analytic operator function, arising in the presentation theory of A.V.~Strauss.