Curvature Condition for Non-contractions Does Not Imply Similarity to the Backward Shift. Hyun-kyoung Kwon and Sergei Treil
نویسنده
چکیده
We give an example of an operator that satisfies the curvature condition as defined in [2], but is not similar to the backward shift S ∗ on the Hardy class H. We conclude therefore that the contraction assumption in the similarity characterization given in [2] is a necessary requirement.
منابع مشابه
Similarity of Operators and Geometry of Eigenvector Bundles
We characterize the contractions that are similar to the backward shift in the Hardy space H. This characterization is given in terms of the geometry of the eigenvector bundles of the operators.
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