On the radius of a set in a Hilbert space. (English) Zbl 0568.46018

Daneš, Josef

Commentat. Math. Univ. Carol. 25, 355-362 (1984).

For a detailed review of the preliminary communication of this paper see [Abh. Akad. Wiss. DDR, Abt. Math., Naturwiss. Tech. 1981, Nr. 2N, 337-338 (1981; Zbl 0469.46020).

MSC:

46C05	Hilbert and pre-Hilbert spaces: geometry and topology (including spaces with semidefinite inner product)
47H10	Fixed-point theorems
52A40	Inequalities and extremum problems involving convexity in convex geometry

Keywords:

radius and center of a set; measure of noncompactness

Citations:

Zbl 0469.46020