Mathematical Notes

, Volume 80, Issue 1–2, pp 224–232 | Cite as

An infinite-dimensional generalization of the Jung theorem

  • V. Nguen-Khac
  • K. Nguen-Van


A complete characterization of the extremal subsets of Hilbert spaces, which is an infinite-dimensional generalization of the classical Jung theorem, is given. The behavior of the set of points near the Chebyshev sphere of such a subset with respect to the Kuratowski and Hausdorff measures of noncompactness is investigated.

Key words

Jung theorem Jung constant extremal subset of a Hilbert space Chebyshev sphere Kuratowski and Hausdorff noncompactness measures 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • V. Nguen-Khac
    • 1
  • K. Nguen-Van
    • 2
  1. 1.Institute of MathematicsHanoiVietnam
  2. 2.Hanoi Pedagogical instituteHanoiVietnam

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