Line transversals to disjoint balls

被引:9
作者
Borcea, Ciprian [1 ]
Goaoc, Xavier [2 ]
Petitjean, Sylvain [3 ]
机构
[1] Rider Univ, Lawrenceville, NJ 08648 USA
[2] LORIA, INRIA Lorraine, Nancy, France
[3] LORIA, CNRS, Nancy, France
关键词
transversal; geometric permutation; convexity;
D O I
10.1007/s00454-007-9016-z
中图分类号
TP301 [理论、方法];
学科分类号
081202 ;
摘要
We prove that the set of directions of lines intersecting three disjoint balls in R-3 in a given order is a strictly convex subset of S-2. We then generalize this result to n disjoint balls in R-d. As a consequence, we can improve upon several old and new results on line transversals to disjoint balls in arbitrary dimension, such as bounds on the number of connected components and Helly-type theorems.
引用
收藏
页码:158 / 173
页数:16
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