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arXiv · 2210.10178

Phelps Property U and $C(K)$ spaces

Ch. Cobollo·A. J. Guirao·V. Montesinos
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Abstract

A subspace $X$ of a Banach space $Y$ has $\textit{Property U}$ whenever every continuous linear functional on $X$ has a unique norm-preserving (i.e., Hahn$-$Banach) extension to $Y$ (Phelps, 1960). Throughout this document we introduce and develop a systematic study of the existence of $\textit{U-embeddings}$ between Banach spaces $X$ and $Y$, that is, isometric embeddings of $X$ into $Y$ whose ranges have property U. In particular, we are interested in the case that $Y=C(K)$, where $K$ is a compact Hausdorff topological space. We provide results for general Banach spaces and for some specific set-ups, such as $X$ being a finite-dimensional space or a $C(K)$-space.

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Ch. Cobollo, A. J. Guirao, V. Montesinos. 2022-10-18. Phelps Property U and $C(K)$ spaces. https://arxiv.org/abs/2210.10178

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