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arXiv · 2004.12610

Isometric dilations of commuting contractions and Brehmer positivity

Sibaprasad Barik·B. Krishna Das
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Abstract

It is well-known that an $n$-tuple $(n\ge 3)$ of commuting contractions does not posses an isometric dilation, in general. Considering a class of $n$-tuple of commuting contractions satisfying certain positivity assumption, we construct their isometric dilations and consequently establish their von Neumann inequality. The positivity assumption is related to Brehmer positivity and motivated by the study of isometric dilations of operator tuples in [4].

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Sibaprasad Barik, B. Krishna Das. 2020-04-27. Isometric dilations of commuting contractions and Brehmer positivity. https://arxiv.org/abs/2004.12610

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