论文标题
逆最大和平均距离最小化问题
Inverse maximal and average distance minimizer problems
论文作者
论文摘要
考虑一个紧凑型$ M \ subset \ mathbb {r}^d $和$ r> 0 $。最大距离最小化的问题是找到最小长度的连接的紧凑型$σ$,以便\ [\ max_ {y \ in m} dist(y,σ)\ leq r。 \]逆问题是确定给定的紧凑型连接集$σ$是否是一种紧凑的$ m $和一些正$ r $的最小化器。 让Steiner Tree $ st $带有$ N $终端的终端顶点是独一无二的。本文的第一个结果是,$ st $是$ m $ n $点的最小化器和足够小的正$ r $。众所周知,在平面案例中,一般的施泰纳树(在有限数量的终端上)是独一无二的。值得注意的是,对于任何$ n $ n $ n $ m $,以$ n = 4 $开头的任何$ n $ set set $ m $,$ n $终端顶点上的斯坦纳树不是最小化的;最简单的示例是一个正方形顶点的坦者树。 众所周知,平面最大距离最小化器是简单曲线的有限结合。第二个结果是一个最小化器的示例,具有无限数量的角点(具有两个切线射线的点,不属于同一线),这意味着该最小化器不能表示为平滑曲线的有限结合。 我们的第三个结果是,每个注射$ c^{1,1} $ - 曲线$σ$是一个足够小的$ r> 0 $和$ m = \ overline {b_r(σ)} $的最小化器。该证明是基于Tilli在平均距离最小化器中产生的类似物。最后,我们将蒂利(Tilli)从飞机的结果推广到$ d $维的欧几里得空间。
Consider a compact $M \subset \mathbb{R}^d$ and $r > 0$. A maximal distance minimizer problem is to find a connected compact set $Σ$ of the minimal length, such that \[ \max_{y \in M} dist (y, Σ) \leq r. \] The inverse problem is to determine whether a given compact connected set $Σ$ is a minimizer for some compact $M$ and some positive $r$. Let a Steiner tree $St$ with $n$ terminals be unique for its terminal vertices. The first result of the paper is that $St$ is a minimizer for a set $M$ of $n$ points and a small enough positive $r$. It is known that in the planar case a general Steiner tree (on a finite number of terminals) is unique. It is worth noting that a Steiner tree on $n$ terminal vertices can be not a minimizer for any $n$ point set $M$ starting with $n = 4$; the simplest such example is a Steiner tree for the vertices of a square. It is known that a planar maximal distance minimizer is a finite union of simple curves. The second result is an example of a minimizer with an infinite number of corner points (points with two tangent rays which do not belong to the same line), which means that this minimizer can not be represented as a finite union of smooth curves. Our third result is that every injective $C^{1,1}$-curve $Σ$ is a minimizer for a small enough $r>0$ and $M = \overline{B_r(Σ)}$. The proof is based on analogues result by Tilli on average distance minimizers. Finally, we generalize Tilli's result from the plane to $d$-dimensional Euclidean space.