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arXiv · 2304.07968

Lifting Brownian-type operators with subnormal entry

Sameer Chavan·Zenon Jan Jablonski·Il Bong Jung·Jan Stochel
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Abstract

In this paper, we study Brownian-type operators, which are upper triangular $2\times 2$ block matrix operators with entries satisfying some algebraic constraints. We establish a lifting theorem stating that any Brownian-type operator with subnormal $(2,2)$ entry lifts to a Brownian-type operator with normal $(2,2)$ entry, where lifting is understood in the sense of extending entries of the block matrices representing the operators in question. The spectral inclusion and the filling in holes theorems are obtained for such operators.

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BibTeXRIS

Sameer Chavan, Zenon Jan Jablonski, Il Bong Jung, Jan Stochel. 2023-04-17. Lifting Brownian-type operators with subnormal entry. https://arxiv.org/abs/2304.07968

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