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تسجيل مستخدم جديدEvery 2-dimensional Banach space has the Mazur-Ulam property
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تأليف
Taras Banakh
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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 Tingleys problem in the class of 2-dimensional Banach spaces.
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A Banach space $X$ has the $Mazur$-$Ulam$ $property$ if any isometry from the unit sphere of $X$ onto the unit sphere of any other Banach space $Y$ extends to a linear isometry of the Banach spaces $X,Y$. A Banach space $X$ is called $smooth$ if the
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