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arXiv · 2509.16969

Isometric and Quasi-isometric weighted composition operators

M. S. Al Ghafri·Y. Estaremi·M. Z. Gashti
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Abstract

In this paper we characterize $m$-isometric and quasi-$m$-isometric weighted composition operators on the Hilbert space $L^2(\mu)$. Also, we find that normal-$m$-isometry and normal quasi-$m$-isometry weighted composition operators have finite spectrum. Consequently we have the results for composition and multiplication operators. In addition, we prove that for $m\geq 2$, a multiplication operator is $m$-isometry (quasi-$m$-isometry) if and only if it is $2$-isometry (quasi-$2$-isometry). Some examples are provided to illustrate our results.

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M. S. Al Ghafri, Y. Estaremi, M. Z. Gashti. 2025-09-21. Isometric and Quasi-isometric weighted composition operators. https://arxiv.org/abs/2509.16969

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