English

On isometric reflexions in Banach spaces

Functional Analysis 2016-09-06 v1

Abstract

We obtain the following characterization of Hilbert spaces. Let EE be a Banach space whose unit sphere SS has a hyperplane of symmetry. Then EE is a Hilbert space iff any of the following two conditions is fulfilled: a) the isometry group IsoE{\rm Iso}\, E of EE has a dense orbit in S; b) the identity component G0G_0 of the group IsoE{\rm Iso}\, E endowed with the strong operator topology acts topologically irreducible on EE. Some related results on infinite dimentional Coxeter groups generated by isometric reflexions are given which allow to analyse the structure of isometry groups containing sufficiently many reflexions.

Keywords

Cite

@article{arxiv.math/9512204,
  title  = {On isometric reflexions in Banach spaces},
  author = {A. Skorik and Mikhail Zaidenberg},
  journal= {arXiv preprint arXiv:math/9512204},
  year   = {2016}
}
R2 v1 2026-07-22T17:55:54.617Z