Proceedings of the American Mathematical Society

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ISSN 1088-6826(e) ISSN 0002-9939(p)

Polynomially bounded operators and Ext groups

Author(s): Sarah H. Ferguson
Journal: Proc. Amer. Math. Soc. 124 (1996), 2779-2785.
MSC (1991): Primary 47B38; Secondary 18G15
MathSciNet review: 1327011
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Abstract | References | Similar articles | Additional information

Abstract: In this paper, we consider the Ext functor in the category
of Hilbert modules over the disk algebra. We characterize the group
$\operatorname {Ext}_{A(D)}(K,H)$ as a quotient of operators and explicitly calculate
$\operatorname {Ext}_{A(D)}(K,% H^{2})$ , where $K$ is a weighted Hardy space. We then use our results to give a simple proof of a result due to Bourgain.

References:

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