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arXiv · 0803.4243

Hyperspace of convex compacta of nonmetrizable compact convex subspaces of locally convex spaces

Lidia Bazylevych·Dušan Repovš·Michael Zarichnyi
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Abstract

Our main result states that the hyperspace of convex compact subsets of a compact convex subset $X$ in a locally convex space is an absolute retract if and only if $X$ is an absolute retract of weight $\leω_1$. It is also proved that the hyperspace of convex compact subsets of the Tychonov cube $I^{ω_1}$ is homeomorphic to $I^{ω_1}$. An analogous result is also proved for the cone over $I^{ω_1}$. Our proofs are based on analysis of maps of hyperspaces of compact convex subsets, in particular, selection theorems for such maps are proved.

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Lidia Bazylevych, Dušan Repovš, Michael Zarichnyi. 2008-03-29. Hyperspace of convex compacta of nonmetrizable compact convex subspaces of locally convex spaces. https://doi.org/10.1016/j.topol.2007.02.014

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