Title
Distance k-sectors exist☆
Abstract
The bisector of two nonempty sets P and Q in a metric space is the set of all points with equal distance to P and to Q. A distance k-sector of P and Q, where k is an integer, is a (k-1)-tuple (C_1, C_2, ..., C_{k-1}) such that C_i is the bisector of C_{i-1} and C_{i+1} for every i = 1, 2, ..., k-1, where C_0 = P and C_k = Q. This notion, for the case where P and Q are points in Euclidean plane, was introduced by Asano, Matousek, and Tokuyama, motivated by a question of Murata in VLSI design. They established the existence and uniqueness of the distance trisector in this special case. We prove the existence of a distance k-sector for all k and for every two disjoint, nonempty, closed sets P and Q in Euclidean spaces of any (finite) dimension, or more generally, in proper geodesic spaces (uniqueness remains open). The core of the proof is a new notion of k-gradation for P and Q, whose existence (even in an arbitrary metric space) is proved using the Knaster-Tarski fixed point theorem, by a method introduced by Reem and Reich for a slightly different purpose.
Year
DOI
Venue
2010
10.1016/j.comgeo.2010.05.001
Computational Geometry: Theory and Applications
Keywords
Field
DocType
arbitrary metric space,special case,proper geodesic space,metric space,euclidean plane,distance k-sectors,equal distance,distance k-sector,new notion,euclidean space,distance trisector,vlsi design,fixed point theorem
Integer,Discrete mathematics,Uniqueness,Combinatorics,Disjoint sets,Closed set,Euclidean geometry,Metric space,Mathematics,Geodesic,Fixed-point theorem
Journal
Volume
Issue
ISSN
43
9
Computational Geometry 43(9):713-720, November 2010
Citations 
PageRank 
References 
1
0.37
7
Authors
5
Name
Order
Citations
PageRank
Keiko Imai18316.53
Akitoshi Kawamura210215.84
Jiří Matoušek31711179.65
Daniel Reem4779.11
Takeshi Tokuyama51179417.31