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arXiv · 1104.4428

Normal extensions escape from the class of weighted shifts on directed trees

Zenon Jan Jablonski·Il Bong Jung·Jan Stochel
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Abstract

A formally normal weighted shift on a directed tree is shown to be a bounded normal operator. The question of whether a normal extension of a subnormal weighted shift on a directed tree can be modeled as a weighted shift on some, possible different, directed tree is answered.

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Zenon Jan Jablonski, Il Bong Jung, Jan Stochel. 2011-04-22. Normal extensions escape from the class of weighted shifts on directed trees. https://arxiv.org/abs/1104.4428

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