Absolutely proximinal subspaces of Banach spaces

Strongly Proximinal Subspaces in Banach Spaces

We give descriptions of SSDand QP -points in C(K)-spaces and use this to characterize strongly proximinal subspaces of finite codimension in L1(μ). We provide some natural class of examples of strongly proximinal subspaces which are not necessarily finite codimensional. We also study transitivity of strong proximinal subspaces of finite codimension.

On the Proximinality of the Unit Ball of Proximinal Subspaces in Banach Spaces: a Counterexample

A known, and easy to establish, fact in Best Approximation Theory is that, if the unit ball of a subspace G of a Banach space X is proximinal in X, then G itself is proximinal in X. We are concerned in this article with the reverse implication, as the knowledge of whether the unit ball is proximinal or not is useful in obtaining information about other problems. We show, by constructing a count...

Proximinal and Strongly Proximinal Subspaces of Finite codimension

Let X be a normed linear space. We will consider only normed linear spaces over R (Real line), though many of the results we describe hold good for n.l. spaces over C (the complex plane). The dual of X, the class of all bounded, linear functionals on X, is denoted by X∗. The closed unit ball of X is denoted by BX and the unit sphere, by SX . That is, BX = {x ∈ X : ‖x‖ ≤ 1} and SX = {x ∈ X : ‖x‖...

On quasi-complemented subspaces of banach spaces.

BANACH SPACES OF POLYNOMIALS AS “LARGE” SUBSPACES OF l∞-SPACES

In this note we study Banach spaces of traces of real polynomials on R to compact subsets equipped with supremum norms from the point of view of Geometric Functional Analysis.