Let X be a Banach space. Given M a subspace of X we denote with P M the metric projection onto M. We define ?(X ) :=sup [&P M &: M a proximinal subspace of X]. In this paper we give a bound for ?(X ). In particular, when X=L p , we obtain the inequality &P M & 2 |2Γ p&1| , for every subspace M of L
A Note on Metric Projections
β Scribed by F. Mazzone; H. Cuenya
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 147 KB
- Volume
- 81
- Category
- Article
- ISSN
- 0021-9045
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β¦ Synopsis
In this note we give an example of a strictly convex, reflexive, smooth Banach space which has a Chebyshev subspace (M), such that the projection onto (M) is linear and has norm equal to 2 . Moreover, we give necessary and sufficient conditions on a space so that every projection has norm less than a constant which is less than 2. Ci 1995 Academic Press. Inc.
π SIMILAR VOLUMES
## Abstract We show that all graphs with a simple extension property are projective. As a consequence of this result we settle in the affirmative a conjecture of Larose and Tardif and characterize all homogeneous graphs which are projective. Β© 2004 Wiley Periodicals, Inc. J Graph Theory 47: 81β86,
## Abstract We investigate the consequences of removing the infinitary axiom and rules from a previously defined proof system for a fragment of propositional metric temporal logic over dense time (see [1]). (Β© 2006 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)
In this note it is shown that the \(L_{1}\) metric projection onto a lattice is Lipschitz continuous, and that it has a Lipschitz continuous selection. (1) 1994 Academic Press, Inc.