Speaker: Michiya Mori (Univ. Tokyo)

Title: On the Scottish Book Problem 155 by Mazur and Sternbach

Time/Date: 4:45-6:15pm, November 14 (Tue), 2023.

Room: 128 Math Sci Building (It will be also online. The Zoom link is the same as before. If you don't have one, please ask Kawahigashi.)

Abstract: Problem 155 of the Scottish Book asks whether every bijection U between two Banach spaces X, Y with the property that, each point of X has a neighborhood on which U is isometric, is globally isometric on X. We prove that this is true under the additional assumption that X is separable and the weaker assumption of surjectivity instead of bijectivity.