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arXiv · 2608.07146

Birkhoff-Orthogonal Takahashi-von Neumann-Jordan Type Constants in Banach Spaces

Junxiang Qi·Zhouping Yin·Qi Liu
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Abstract

In this paper, we introduce a new family of geometric constants CtB(X) of Birkhoff-orthogonal Takahashi-von Neumann-Jordan type for real Banach spaces. We discuss their basic properties and give a characterization of uniformly non-square spaces via CtB(X). Some sufficient conditions for super-reflexivity and fixed point property are presented. We establish upper bounds of CtB(X) related to orthogonal geometric moduli and constants, and obtain the sharp value for Radon planes.

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BibTeXRIS

Junxiang Qi, Zhouping Yin, Qi Liu. 2026-08-07. Birkhoff-Orthogonal Takahashi-von Neumann-Jordan Type Constants in Banach Spaces. https://arxiv.org/abs/2608.07146

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