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arXiv 1512.02449math.MG
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随机逼近与凸体的顶点指数

Random approximation and the vertex index of convex bodies

Silouanos Brazitikos, Giorgos Chasapis, Labrini Hioni

摘要:

本文证明了存在一个具有以下性质的绝对常数$α>1$:如果$K$是${\mathbb R}^n$中的一个凸体,其质心在原点,则基数为${\rm card}(X)=\lceilαn\rceil $的随机子集$X\subset K$以大于$1-e^{-n}$的概率满足{K \subseteq c_1n\,{ \mathrm conv}(X),}其中$c_1>0$是一个绝对常数.作为应用,我们证明了在${\mathbb R}^n$中的任意凸体$K$的顶点指数都是由$c_2n^2$限定的,其中$c_2>0$是一个绝对常数,从而推广了Bezdek和Litvak对对称情形的一个估计.

英文摘要:

We prove that there exists an absolute constant $α>1$ with the following property: if $K$ is a convex body in ${\mathbb R}^n$ whose center of mass is at the origin, then a random subset $X\subset K$ of cardinality ${\rm card}(X)=\lceilαn\rceil $ satisfies with probability greater than $1-e^{-n}$ {K\subseteq c_1n\,{\mathrm conv}(X),} where $c_1>0$ is an absolute constant. As an application we show that the vertex index of any convex body $K$ in ${\mathbb R}^n$ is bounded by $c_2n^2$, where $c_2>0$ is an absolute constant, thus extending an estimate of Bezdek and Litvak for the symmetric case.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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