Approximation of smooth convex bodies by random polytopes

Julian Grote; Elisabeth M. Werner

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arXiv · 1706.07623

Approximation of smooth convex bodies by random polytopes

Julian Grote·Elisabeth M. Werner

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Abstract

Let $K$ be a convex body in $\mathbb{R}^n$ and $f : \partial K \rightarrow \mathbb{R}_+$ a continuous, strictly positive function with $\int\limits_{\partial K} f(x) d \mu_{\partial K}(x) = 1$. We give an upper bound for the approximation of $K$ in the symmetric difference metric by an arbitrarily positioned polytope $P_f$ in $\mathbb{R}^n$ having a fixed number of vertices. This generalizes a result by Ludwig, Sch\"utt and Werner $[36]$. The polytope $P_f$ is obtained by a random construction via a probability measure with density $f$. In our result, the dependence on the number of vertices is optimal. With the optimal density $f$, the dependence on $K$ in our result is also optimal.

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Julian Grote, Elisabeth M. Werner. 2017-06-23. Approximation of smooth convex bodies by random polytopes. https://arxiv.org/abs/1706.07623

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