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arXiv · 2605.21555

Partially isometric truncated and dual truncated Toeplitz operators

Kritika Babbar·Mo Javed·Amit Maji
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Abstract

Let $\theta$ be a non-constant inner function and let $\phi=\overline{u}v$, where $u$ and $v$ are inner functions such that $v$ divides $\theta$. In this paper we characterize the partially isometric truncated Toeplitz operators $A_{\phi}$ and dual truncated Toeplitz operators $D_{\phi}$ with symbols of the form $\phi=\overline{u}v$. Along with that, we obtain a few more characterization results, including the space of extremal vectors for non-zero partially isometric truncated and dual truncated Toeplitz operators.

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Kritika Babbar, Mo Javed, Amit Maji. 2026-05-20. Partially isometric truncated and dual truncated Toeplitz operators. https://arxiv.org/abs/2605.21555

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