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arXiv · 1012.0942

Canonical Models For Bi-Isometries

Hari Bercovici·Ronald G. Douglas·Ciprian Foias
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Abstract

A canonical model, analogous to the one for contraction operators, is introduced for bi-isometries, two commuting isometries on a Hilbert space. This model involves a contractive analytic operator-valued function on the unit disk. Various pureness conditions are considered as well as bi-isometries for which both isometries are shifts. Several families of examples are introduced and classified.

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Hari Bercovici, Ronald G. Douglas, Ciprian Foias. 2010-12-04. Canonical Models For Bi-Isometries. https://arxiv.org/abs/1012.0942

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