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arXiv · 2608.20800

Busemann G-spaces with convex balls

Tadashi Fujioka·Shijie Gu
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Abstract

We prove that any Busemann G-space such that every sufficiently small metric ball is convex is a topological manifold. The key ingredient in the proof is Ivanov's Helly theorem. The appendix contains a counterexample to a question of Berestovskii--Halverson--Repovš.

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Tadashi Fujioka, Shijie Gu. 2026-09-14. Busemann G-spaces with convex balls. https://arxiv.org/abs/2608.20800

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