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Nov 3, 2014 at 19:02 comment added petrbel There are examples that show the set of extreme points of a compact convex subset of a locally convex topological vector space need not be closed when the real dimension of the space is at least 3 - is that so? Where can one find some example of that set? For me it seems impossible to exists.
Apr 3, 2011 at 20:43 comment added Greg Kuperberg @Pete For instance, the convex hull of the four points $(\pm 1, \pm 1, 0)$ and the unit circle in the $x$-$z$ plane.
Jan 25, 2010 at 14:45 answer added Ady timeline score: 1
Jan 5, 2010 at 16:55 comment added Pete L. Clark Thanks for your responses. I deleted my original question, which was rather silly: somehow, in your perfectly clear 2.5 line answer, I missed the part where you used the 2-dimensionality. But I think it's good to have an example of the failure of closedness in higher dimensions.
Jan 5, 2010 at 14:11 comment added Harald Hanche-Olsen Retagged the question – banach-spaces out, convexity in.
Jan 5, 2010 at 14:10 history edited Harald Hanche-Olsen
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Jan 5, 2010 at 8:01 vote accept Mike Hartglass
Jan 5, 2010 at 8:01 vote accept Mike Hartglass
Jan 5, 2010 at 8:01
Jan 5, 2010 at 7:38 answer added 002 timeline score: 9
Jan 5, 2010 at 7:14 history asked Mike Hartglass CC BY-SA 2.5