Two new examples of Banach spaces with a plastic unit ball
نویسندگان
چکیده
We prove that Banach spaces ℓ1 ⊕2 R and X ⊕∞ Y , with strictly convex have plastic unit balls (we call a metric space if every non-expansive bijection from this onto itself is an isometry).
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ژورنال
عنوان ژورنال: Acta et commentationes Universitatis Tartuensis de mathematica
سال: 2022
ISSN: ['1406-2283', '2228-4699']
DOI: https://doi.org/10.12697/acutm.2022.26.07