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arXiv · 1510.07292

Random ball-polyhedra and inequalities for intrinsic volumes

Grigoris Paouris·Peter Pivovarov
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Abstract

We prove a randomized version of the generalized Urysohn inequality relating mean-width to the other intrinsic volumes. To do this, we introduce a stochastic approximation procedure that sees each convex body K as the limit of intersections of Euclidean balls of large radii and centered at randomly chosen points. The proof depends on a new isoperimetric inequality for the intrinsic volumes of such intersections. If the centers are i.i.d. and sampled according to a bounded continuous distribution, then the extremizing measure is uniform on a Euclidean ball. If one additionally assumes that the centers have i.i.d. coordinates, then the uniform measure on a cube is the extremizer. We also discuss connections to a randomized version of the extended isoperimetric inequality and symmetrization techniques.

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Grigoris Paouris, Peter Pivovarov. 2016-06-29. Random ball-polyhedra and inequalities for intrinsic volumes. https://arxiv.org/abs/1510.07292

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