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Unit Distances in Three Dimensions

Published online by Cambridge University Press:  25 April 2012

HAIM KAPLAN
Affiliation:
School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel (e-mail: [email protected])
JIŘÍ MATOUŠEK
Affiliation:
Department of Applied Mathematics and Institute of Theoretical Computer Science (ITI), Charles University, Malostranské nám. 25, 118 00 Praha 1, Czech Republic (e-mail: [email protected]) and Institute of Theoretical Computer Science, ETH Zurich, 8092 Zurich, Switzerland
ZUZANA SAFERNOVÁ
Affiliation:
Department of Applied Mathematics, Charles University, Malostranské nám. 25, 118 00 Praha 1, Czech Republic (e-mail: [email protected])
MICHA SHARIR
Affiliation:
School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel and Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA (e-mail: [email protected])

Abstract

We show that the number of unit distances determined by n points in ℝ3 is O(n3/2), slightly improving the bound of Clarkson, Edelsbrunner, Guibas, Sharir and Welzl [5], established in 1990. The new proof uses the recently introduced polynomial partitioning technique of Guth and Katz [12]. While this paper was still in a draft stage, a similar proof of our main result was posted to the arXiv by Joshua Zahl [28].

Keywords

Type
Paper
Copyright
Copyright © Cambridge University Press 2012

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