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Note on the Curvature and Index of Almost Unitary Contraction Operator

R. N. Levy
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Abstract

In the recent preprint (OA/0006224) S. Parrott proved the equality between the Arveson`s curvature and the Fredholm index of a "pure" contraction with finite defect numbers. In the present note one derives a similar formula in the "non-pure" case.

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R. N. Levy. 2000-12-04. Note on the Curvature and Index of Almost Unitary Contraction Operator. https://arxiv.org/abs/math/0007178

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