Abstract
A homomorphic map is defined from the algebra of norm bounded analyticN-operator valued functions in the unit disc into the algebra of bounded operators in Hilbert spaces represented as left invariant subspaces ofH 2(N), and the spectral properties of the map are studied.
The subclass of functions having norm bound one in the disc is characterized in terms of the power series coefficients.
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This paper was partially supported by the National Science Foundation under contract NSF GP-5455.
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Fuhrmann, P.A. A functional calculus in hilbert space based on operator valued analytic functions. Israel J. Math. 6, 267–278 (1968). https://doi.org/10.1007/BF02760259
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DOI: https://doi.org/10.1007/BF02760259