Sufficient Enlargements in the Study of Projections in Normed Linear Spaces
نویسنده
چکیده
The study of sufficient enlargements of unit balls of Banach spaces forms a natural line of attack of some well-known open problems of Banach space theory. The purpose of the paper is to present known results on sufficient enlargements and to state some open problems.
منابع مشابه
2 00 2 Projections in Normed Linear Spaces and Sufficient Enlargements
Definition. A symmetric with respect to 0 bounded closed convex set A in a finite dimensional normed space X is called a sufficient enlargement for X (or of B(X)) if for arbitrary isometric embedding of X into a Banach space Y there exists a projection P : Y → X such that P (B(Y)) ⊂ A (by B we denote the unit ball). The main purpose of the present paper is to continue investigation of sufficien...
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