Ball intersection properties in metric spaces
نویسندگان
چکیده
The goal of the present work is to introduce new metric space techniques study intersection properties families balls. These add, on one hand, results due Lindenstrauss extension uniformly continuous functions and compact linear operators, answer, other questions raised by Aronszajn Panitchpakdi hyperconvex spaces. divided into two parts. In first part, proofs our main ball in spaces are presented. result states that for any integer [Formula: see text] greater or equal three, a complete almost[Formula: text]-hyperconvex automatically text]-hyperconvex. second shows spaces, property being equivalent finitely analogues true externally[Formula: weakly subsets. This last proved later this unify analysis those three properties: hyperconvexity, external hyperconvexity weak hyperconvexity. part work, we make link with notions convexity bicombings applications. We extend local-to-global externally as well conclude applications characterization subsets
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ژورنال
عنوان ژورنال: Journal of Topology and Analysis
سال: 2021
ISSN: ['1793-7167', '1793-5253']
DOI: https://doi.org/10.1142/s1793525321500400