Abstract
For a Banach space X, a new constant G(X)=sup {λ(X) | A ⊂ X, d(A)=1} is introduced. The main result is that G (X) coincides with the Jung constant J (X) (Theorem 1), which yields an estimate for the latter. Some other results concerning J (X) and the measure of nonconvexity λ are given. Bibliography: 5 titles.
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Additional information
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 208, 1993, pp. 174–181.
Translated by O. A. Ivanov.
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Gulevich, N.M. The measure of nonconvexity and the jung constant. J Math Sci 81, 2562–2566 (1996). https://doi.org/10.1007/BF02362426
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DOI: https://doi.org/10.1007/BF02362426