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arXiv · 2103.09268

Every 2-dimensional Banach space has the Mazur-Ulam property

Taras Banakh
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Abstract

We prove that every isometry between the unit spheres of 2-dimensional Banach spaces extends to a linear isometry of the Banach spaces. This resolves the famous Tingley's problem in the class of 2-dimensional Banach spaces.

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Taras Banakh. 2021-03-16. Every 2-dimensional Banach space has the Mazur-Ulam property. https://doi.org/10.1016/j.laa.2021.09.020

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