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Projections in Certain Continuous Function Spaces C(H) and Subspaces of C(H) Isomorphic with C(H)

Published online by Cambridge University Press:  20 November 2018

David W. Dean*
Affiliation:
Duke University
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If A and B are sets then AB = {x| x £A, x ∉ B}. This notation is also used if A and B are linear spaces. If X and Y are Banach spaces an embedding of X into Y is a continuous linear mapping u of X onto a closed subspace of F which is 1 — 1. In this case X is said to be embedded in Y. If |ux| = |x| for every xX (| … | stands for norm), then u embeds Xisometrically into Y. If u is onto then X and Y are isomorphic and if, in addition, |ux| = |x| for every x ∈ X, then X and Y are isometric. Then an embedding u has a continuous inverse u-1 (4, p. 36) defined on uX and this fact is used below without further reference. The conjugate space of X is denoted by X′. Unless otherwise noted, all topological spaces considered are Hausdorff spaces.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1962

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