English

A Characterization of Extremal Sets in Hilbert Spaces

Metric Geometry 2007-05-23 v3 Functional Analysis

Abstract

We give a characterization of extremal sets in Hilbert spaces that generalizes a classical theorem of H. W. E. Jung. We investigate also the behaviour of points near to the circumsphere of such a set with respect to the Kuratowski and Hausdorff measures of non-compactness.

Keywords

Cite

@article{arxiv.math/0203190,
  title  = {A Characterization of Extremal Sets in Hilbert Spaces},
  author = {V. NguyenKhac and K. NguyenVan},
  journal= {arXiv preprint arXiv:math/0203190},
  year   = {2007}
}

Comments

10 pages, corrected some misprints

R2 v1 2026-07-22T16:44:02.948Z