Continuity of the Metric Projection and Local Solar Properties of Sets

A. R. Alimov1,2
1Faculty of Mechanics and Mathematics, Moscow State University, Moscow, Russia
2Steklov Mathematical Institute, Russian Academy of Sciences, Moscow, Russia

Tóm tắt

The paper is concerned with local approximative and geometric properties of sets, with particular emphasis on strict solarity of such sets under certain constraints on the continuity of metric projections. A partial answer is given to the question due to B. Brosowski and F. Deutsch as to when the class of strict protosuns (Kolmogorov sets) coincides with the class of sets with outer radially continuous metric projection. The lower semi-continuous metric projection with monotone path-connected values is shown to have a continuous selection. A number of related results is obtained.

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Tài liệu tham khảo

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