Weak Chebyshev subspaces and -subspaces of

Author:
Wu Li

Journal:
Trans. Amer. Math. Soc. **322** (1990), 583-591

MSC:
Primary 41A50; Secondary 41A52

DOI:
https://doi.org/10.1090/S0002-9947-1990-1010886-6

MathSciNet review:
1010886

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Abstract: In this paper we show some very interesting properties of weak Chebyshev subspaces and use them to simplify Pinkus's characterization of subspaces of . As a consequence we obtain that if the metric projection from onto a finite-dimensional subspace has a continuous selection and elements of have no common zeros on , then is an -subspace.

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9947-1990-1010886-6

Keywords:
-subspace,
weak Chebyshev subspace,
Chebyshev subspace,
metric projection,
continuous metric selection

Article copyright:
© Copyright 1990
American Mathematical Society