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arXiv · 0710.5396

Gruenhage compacta and strictly convex dual norms

Richard J. Smith
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Abstract

We prove that if K is a Gruenhage compact space then C(K)* admits an equivalent, strictly convex dual norm. As a corollary, we show that if X is a Banach space and X* is the |.|-closed linear span of K, where K is a Gruenhage compact in the w*-topology and |.| is equivalent to a coarser, w*-lower semicontinuous norm on X*, then X* admits an equivalent, strictly convex dual norm. We give a partial converse to the first result by showing that if T is a tree, then C(T)* admits an equivalent, strictly convex dual norm if and only if T is a Gruenhage space. Finally, we present some stability properties satisfied by Gruenhage spaces; in particular, Gruenhage spaces are stable under perfect images.

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Richard J. Smith. 2007-10-29. Gruenhage compacta and strictly convex dual norms. https://doi.org/10.1016/j.jmaa.2008.07.017

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