Abstract
We consider the distance function (DF), given by the caliber (the Minkowski gauge function) of a convex body, from a point to strictly, strongly, and weakly convex sets in an arbitrary Hilbert space. Some properties of the caliber of a strongly convex set and the conditions for obtaining a strict, strong, or weak convexity of Lebesgue sets for the distance function are established in accordance with the requirements for the set, the caliber of which specifies the distance function, and the set to which the distance is measured. The corresponding inequalities are obtained that reflect the behavior of the distance function on segments and allow comparing it with strictly, strongly, or weakly convex functions.
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The research is fulfilled under financial support of the Russian Foundation for Basic Research (project no. 18-01-00209a).
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Russian Text © The Author(s), 2020, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika, 2020, No. 5, pp. 22–38.
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Dudov, S.I., Polovinkin, E.S. & Abramova, V.V. Properties of the Distance Function to Strongly and Weakly Convex Sets in a Nonsymmetrical Space. Russ Math. 64, 17–30 (2020). https://doi.org/10.3103/S1066369X20050035
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DOI: https://doi.org/10.3103/S1066369X20050035