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arXiv · 1107.1016

On supporting hyperplanes to convex bodies

Alessio Figalli·Young-Heon Kim·Robert J. McCann
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Abstract

Given a convex set and an interior point close to the boundary, we prove the existence of a supporting hyperplane whose distance to the point is controlled, in a dimensionally quantified way, by the thickness of the convex set in the orthogonal direction. This result has important applications in the regularity theory for Monge-Amp\`ere type equations arising in optimal transportation.

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Alessio Figalli, Young-Heon Kim, Robert J. McCann. 2011-07-06. On supporting hyperplanes to convex bodies. https://arxiv.org/abs/1107.1016

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