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arXiv · 2606.24550

Spectrally $n$-centered operators. I

Piotr Budzyński
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Abstract

We introduce the concept of spectrally $n$-centered operators and study it within the framework of unbounded weighted composition operators in $L^2$-spaces. Based on this, we establish a characterisation of spectrally centered unbounded weighted composition operators, generalising Giselsson's criterion to the unbounded regime. Finally, we analyse various associated conditions, highlighting the delicate measure-theoretic anomalies.

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Piotr Budzyński. 2026-06-23. Spectrally $n$-centered operators. I. https://arxiv.org/abs/2606.24550

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