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When are the closed convex subsets countable intersections of halfspaces
For what kind of topological vector spaces (separable maybe?) are the closed convex subsets countable intersections of halfspaces.
I've seen somewhere that it's true for separable Hilbert spaces, ...
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Convex hulls of compact sets
Let $A$ be a compact set in a separable Hilbert space $H$, and let $\bar A$ denote its convex hull. Is $\bar A$ compact?