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arXiv · 2509.23319

On the equivalent Zb\v{a}ganu constant associated with isosceles orthogonality in Banach spaces

Tingting Hu·Qi Liu·Mengmeng Bao·Yuxin Wang
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Abstract

This paper systematically investigates a new geometric constant associated with isosceles orthogonality in Banach spaces. By establishing the connection between this new constant and a classical function, sharp upper and lower bounds for the constant are derived. Specifically, the space is exactly a Hilbert space when the new constant reaches its lower bound; in finite-dimensional spaces, if the new constant attains its upper bound, it implies that the space does not possess uniform non-squareness.

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Tingting Hu, Qi Liu, Mengmeng Bao, Yuxin Wang. 2025-09-27. On the equivalent Zb\v{a}ganu constant associated with isosceles orthogonality in Banach spaces. https://arxiv.org/abs/2509.23319

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