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MiS Preprint

Non-compact lamination convex hulls

Jan Kolár


We give an example of a compact set K of symmetric two by two matrices such that its lamination convex hull is not compact, and similar examples for separate convexity in R3 and bi-convexity in R2 x R. Furthermore we show that the operator, mapping a compact set onto the closure of its lamination convex hull, is not upper semi-continuous with respect to Hausdorff metric on the space of all compact sets K of diagonal 3 x 3 matrices.

MSC Codes:
26B25, 52A30
lamination convex hull, bi-convexity, separate convexity

Related publications

2003 Repository Open Access
Jan Kolar

Non-compact lamination convex hulls

In: Annales de l'Institut Henri Poincaré / C, 20 (2003) 3, pp. 391-403