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arXiv · 2309.12859

Higher order isometric shift operator on the de Branges-Rovnyak space

Caixing Gu·Shuaibing Luo
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Abstract

The de Branges-Rovnyak space $H(b)$ is generated by a bounded analytic function $b$ in the unit ball of $H^\infty$. When $b$ is a nonextreme point, the space $H(b)$ is invariant by the forward shift operator $M_z$. We show that the $H(b)$ spaces provide model spaces for expansive quasi-analytic $2n$-isometric operators $T$ with $T^*T - I$ being rank one. Then we describe the invariant subspaces of the $2n$-isometric forward shift operator $M_z$ on $H(b)$.

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Caixing Gu, Shuaibing Luo. 2023-09-22. Higher order isometric shift operator on the de Branges-Rovnyak space. https://arxiv.org/abs/2309.12859

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