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arXiv · 2504.20748

On the estimation of the $q$-numerical radius via Orlicz functions

Fuad Kittaneh·Arnab Patra·Jyoti Rani
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Abstract

This study utilizes Orlicz functions to provide refined lower and upper bounds on the q-numerical radius of an operator acting on a Hilbert space. Additionally, the concept of q-sectorial matrices is introduced and further bounds for the q-numerical radius are established. Our results unify several existing bounds for the q-numerical radius. Suitable examples are provided to supplement the estimations.

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Fuad Kittaneh, Arnab Patra, Jyoti Rani. 2025-04-29. On the estimation of the $q$-numerical radius via Orlicz functions. https://arxiv.org/abs/2504.20748

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