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On the Mazur-Ulam theorem and the Aleksandrov problem for unit distance preserving mappings

Authors: Themistocles M. Rassias and Peter Šemrl
Journal: Proc. Amer. Math. Soc. 118 (1993), 919-925
MSC: Primary 46B20; Secondary 51K99, 54E40
MathSciNet review: 1111437
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Abstract: Let $ X$ and $ Y$ be two real normed vector spaces. A mapping $ f:X \to Y$ preserves unit distance in both directions iff for all $ x,y \in X$ with $ \vert\vert x - y\vert\vert = 1$ it follows that $ \vert\vert f(x) - f(y)\vert\vert = 1$ and conversely. In this paper we shall study, instead of isometries, mappings satisfying the weaker assumption that they preserve unit distance in both directions. We shall prove that such mappings are not very far from being isometries. This problem was asked by A. D. Aleksandrov. The first classical result that characterizes isometries between normed real vector spaces goes back to S. Mazur and S. Ulam in 1932. We also obtain an extension of the Mazur-Ulam theorem.

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  • [1] A. D. Alexandrov, Mappings of families of sets, Soviet Math. Dokl. 11 (1970), 116-120.
  • [2] A. Guc, On mappings that preserve a family of sets in Hilbert and hyperbolic spaces, Candidate's Dessertation, Novosibirsk, 1973.
  • [3] S. Mazur et S. Ulam, Sur les transformations isométriques d'espaces vectoriels normés, C. R. Acad. Sci. Paris 194 (1932), 946-948.
  • [4] B. Mielnik and T. M. Rassias, On the Aleksandrov problem of conservative distances, Proc. Amer. Math. Soc. 116 (1992), 1115-1118. MR 1101989 (93b:51020)
  • [5] T. M. Rassias, Is a distance one preserving mapping between metric spaces always an isometry?, Amer. Math. Monthly 90 (1983), 200. MR 1540159
  • [6] -, Some remarks on isometric mappings, Facta Univ. Ser. Math. Inform. 2 (1987), 49-52. MR 963783 (89m:51028)
  • [7] -, Problems, Aequationes Math. 39 (1990), 304.

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