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arXiv · 1802.01386

Curvature Inequalities and Extremal Operators

Gadadhar Misra·Md. Ramiz Reza
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Abstract

A curvature inequality is established for contractive commuting tuples of operators in the Cowen-Douglas class of rank n. Properties of the extremal operators, that is, the operators which achieve equality, are investigated. Specifically, a substantial part of a well known question due to R. G. Douglas involving these extremal operators, in the case of the unit disc, is answered.

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Gadadhar Misra, Md. Ramiz Reza. 2018-02-05. Curvature Inequalities and Extremal Operators. https://doi.org/10.1215/00192082-7768711

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