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Near-Optimal Separators in String Graphs

Published online by Cambridge University Press:  07 October 2013

JIŘÍ MATOUŠEK*
Affiliation:
Department of Applied Mathematics and Institute of Theoretical Computer Science (ITI), Charles University, Malostranské nám. 25, 11800 Praha 1, Czech Republic and Institute of Theoretical Computer Science, ETH Zurich, 8092 Zurich, Switzerland (e-mail: matousek@kam.mff.cuni.cz)

Abstract

Let G be a string graph (an intersection graph of continuous arcs in the plane) with m edges. Fox and Pach proved that G has a separator consisting of $O(m^{3/4}\sqrt{\log m})$ vertices, and they conjectured that the bound of $O(\sqrt m)$ actually holds. We obtain separators with $O(\sqrt m \,\log m)$ vertices.

Type
Paper
Copyright
Copyright © Cambridge University Press 2013 

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