A Remark on M. M. Day's Characterization of Inner-Product Spaces and a Conjecture of L. M. Blumenthal
From MaRDI portal
Publication:5815830
DOI10.2307/2031742zbMath0049.08301OpenAlexW4238799204WikidataQ29300873 ScholiaQ29300873MaRDI QIDQ5815830
Publication date: 1952
Published in: Proceedings of the American Mathematical Society (Search for Journal in Brave)
Full work available at URL: https://doi.org/10.2307/2031742
Related Items
A Characterization of Inner Product Spaces, Some characterizations of inner product spaces via some geometrical inequalities, Möbius rigidity of invariant metrics in boundaries of symmetric spaces of rank-1, Fixed point theorems for some generalized nonexpansive mappings in Ptolemy spaces, Orthogonality Types in Normed Linear Spaces, An Integral Analogue to Parallelogram Law, Characterization of Aleksandrov spaces of curvature bounded above by means of the metric Cauchy-Schwarz inequality, On quasisymmetric mappings in semimetric spaces, Ptolemy spaces with strong inversions, Absolute-Valued Algebras, Geodesic Ptolemy spaces and fixed points, Criteria for Inner Product Spaces, Asymptotic behavior of averaged and firmly nonexpansive mappings in geodesic spaces, Neue Existenz- und Konvergenzsätze in der Fixpunkttheorie nichtlinearer Operatoren, Metric Möbius geometry and a characterization of spheres, Quasilinearization and curvature of Aleksandrov spaces, A note on generalized four-point inequality, Combinatorial characterization of pseudometrics, Ptolemy circles and Ptolemy segments, Möbius characterization of hemispheres, A flat strip theorem for Ptolemaic spaces, Möbius characterization of the boundary at infinity of rank one symmetric spaces, The Ptolemaean inequality in the closure of complexhyperbolic planes, Group actions on geodesic Ptolemy spaces, Cross-ratios and the Ptolemaean inequality in boundaries of symmetric spaces of rank 1, Metric betweenness, Ptolemaic spaces, and isometric embeddings of pretangent spaces in \(\mathbb R\), A notion of nonpositive curvature for general metric spaces, On Ptolemaic metric simplicial complexes, The Ptolemy and Zbăganu constants of normed spaces, A characterization of inner product spaces concerning an Euler-Lagrange identity, Ptolemaic spaces, Characterization of geodesic arcs, Absolute valued algebras containing a central idempotent, A characteristic property of Euclidean spaces, PTOLEMAIC SPACES AND CAT(0), On height orthogonality in normed linear spaces, A note on smooth Banach spaces, On Criteria of Kasahara and Blumenthal for Inner-Product Spaces, Multi-valued version of \(SCC\), \(SKC\), \(KSC\), and \(CSC\) conditions in Ptolemy metric spaces
