Geometric permutations of disjoint unit spheres
نویسندگان
چکیده
We show that a set of n disjoint unit spheres in R admits at most two distinct geometric permutations if n ≥ 9, and at most three if 3 ≤ n ≤ 8. This result improves a Helly-type theorem on line transversals for disjoint unit spheres in R: if any subset of size 18 of a family of such spheres admits a line transversal, then there is a line transversal for the entire family.
منابع مشابه
The Harmony of Spheres
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عنوان ژورنال:
- Comput. Geom.
دوره 30 شماره
صفحات -
تاریخ انتشار 2005