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arXiv · 1509.07908

Helly-type theorems for the diameter

Pablo Soberón
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Abstract

We study versions of Helly's theorem that guarantee that the intersection of a family of convex sets in $R^d$ has a large diameter. This includes colourful, fractional and $(p,q)$ versions of Helly's theorem. In particular, the fractional and $(p,q)$ versions work with conditions where the corresponding Helly theorem does not. We also include variants of Tverberg's theorem, B\'ar\'any's point selection theorem and the existence of weak epsilon-nets for convex sets with diameter estimates.

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Pablo Soberón. 2015-09-25. Helly-type theorems for the diameter. https://arxiv.org/abs/1509.07908

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