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arXiv · 2509.23239

On a class of m-Isometric and Quasi-m-isometric operators

Y. Estaremi·M. S. Al Ghafri·S. Shamsigamchi
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Abstract

In this paper we characterize $m$-isometric and quasi-$m$-isometric weighted conditional type (WCT) operators on the Hilbert space $L^2(\mu)$. Also, we prove that the subclasses of $m$-isometric and quasi-$m$-isometric of normal WCT operators are coincide. Specially we have the results for multiplication operators. Indeed, we find that for $m\geq 2$, a multiplication operator $M_u$ is $m$-isometric (quasi-$m$-isometric) if and only if it is isometric (quasi-isometric). Some examples are provided to illustrate our results.

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Y. Estaremi, M. S. Al Ghafri, S. Shamsigamchi. 2025-09-27. On a class of m-Isometric and Quasi-m-isometric operators. https://arxiv.org/abs/2509.23239

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