Projection constants for $C(S)$ spaces with the separable projection property

Minimal Projections and Absolute Projection Constants for Regular Polyhedral Spaces

Let V« [vx,...,vn] be the «-dimensional space of coordinate functions on a set of points ¡cR" where v is the set of vertices of a regular convex polyhedron. In this paper the absolute projection constant of any «-dimensional Banach space E isometrically isomorphic to V c C(v) is computed, examples of which are the well-known cases E = ITM, lln.

A projection property for buildings

There are two motivations for studying the question whether X has the projection property. Firstly, Arrow's \dictator theorem" states that the only maps of a product X A to X with certain properties are the projections (see A], PRS]). Secondly, the projection property is closely related to the xed point property (see C]). For a detailed discussion of the projection property, its background and ...

Lipschitz Extension Constants Equal Projection Constants

For a Banach space V we define its Lipschitz extension constant, LE(V ), to be the infimum of the constants c such that for every metric space (Z, ρ), every X ⊂ Z, and every f : X → V , there is an extension, g, of f to Z such that L(g) ≤ cL(f), where L denotes the Lipschitz constant. The basic theorem is that when V is finite-dimensional we have LE(V ) = PC(V ) where PC(V ) is the well-known p...

Numerical Estimation of Projection Constants

On Maximal Relative Projection Constants

This article focuses on the maximum of relative projection constants over all m-dimensional subspaces of the N -dimensional coordinate space equipped with the max-norm. This quantity, called maximal relative projection constant, is studied in parallel with a lower bound, dubbed quasimaximal relative projection constant. Exploiting elegant expressions for these quantities, we show how they can b...