Abstract
In the beginning sixties V. L. Klee conjectured that there exist nonconvex Chebyshev sets in an infinite dimensional Hilbert space. Up to today no real progress has been made in proving or disproving the conjecture. The author wants to discuss a modified version of Klees’s conjecture which seems to be of some independent interest.
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© 1981 Birkhäuser Verlag Basel
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Berens, H. (1981). Ein Problem Über die Beste Approximation in Hilberträumen. In: Butzer, P.L., Sz.-Nagy, B., Görlich, E. (eds) Functional Analysis and Approximation. ISNM 60: International Series of Numerical Mathematics / ISNM 60: Internationale Schriftenreihe zur Numerischen Mathematik / ISNM 60: Série internationale d’Analyse numérique, vol 60. Birkhäuser Basel. https://doi.org/10.1007/978-3-0348-9369-5_23
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DOI: https://doi.org/10.1007/978-3-0348-9369-5_23
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