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arXiv · 2603.18405

Lower and upper bounds of joint $(f,\delta)$-numerical radius functions

Zameddin I. Ismailov·Sergei Silvestrov·Pembe Ipek Al
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Abstract

In this study, the classical results on the joint numerical radius for $n$-tuples of Hilbert space operators are extended to the setting of the joint $(f,\delta)$-numerical radius. New and diverse contributions to this area are provided, including novel estimates for the lower and upper bounds of the $(f,\delta)$-numerical radius in the context of sectorial operators.

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Zameddin I. Ismailov, Sergei Silvestrov, Pembe Ipek Al. 2026-03-19. Lower and upper bounds of joint $(f,\delta)$-numerical radius functions. https://arxiv.org/abs/2603.18405

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