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Representations of Hardy Algebras: Absolute Continuity, Intertwiners, and Superharmonic Operators

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Suppose \({\mathcal{T}_{+}(E)}\) is the tensor algebra of a W*-correspondence E and H (E) is the associated Hardy algebra. We investigate the problem of extending completely contractive representations of \({\mathcal{T}_{+}(E)}\) on a Hilbert space to ultra-weakly continuous completely contractive representations of H (E) on the same Hilbert space. Our work extends the classical Sz.-Nagy–Foiaş functional calculus and more recent work by Davidson, Li and Pitts on the representation theory of Popescu’s noncommutative disc algebra.

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Correspondence to Paul S. Muhly.

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The authors gratefully acknowledge support from the U.S.-Israel Binational Science Foundation. The second author gratefully acknowledges additional support from the Lowengart Research Fund.

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Muhly, P.S., Solel, B. Representations of Hardy Algebras: Absolute Continuity, Intertwiners, and Superharmonic Operators. Integr. Equ. Oper. Theory 70, 151–203 (2011). https://doi.org/10.1007/s00020-011-1869-0

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  • DOI: https://doi.org/10.1007/s00020-011-1869-0

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