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Polynomially bounded operators and Ext groups

Author: 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: 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 [Enhancements On Off] (What's this?)

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Additional Information

Sarah H. Ferguson

Keywords: Polynomially bounded operator, Ext groups, reproducing kernel Hilbert space, weighted Hardy space, BMOA
Received by editor(s): March 13, 1995
Communicated by: Palle E. T. Jorgensen
Article copyright: © Copyright 1996 American Mathematical Society

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