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INTERSECTIONS OF MULTICURVES FROM DYNNIKOV COORDINATES

Published online by Cambridge University Press:  03 May 2018

S. ÖYKÜ YURTTAŞ
Affiliation:
Dicle University, Science Faculty, Mathematics Department, 21280, Diyarbakır, Turkey email [email protected]
TOBY HALL*
Affiliation:
Department of Mathematical Sciences, University of Liverpool, Liverpool L69 7ZL, UK email [email protected]
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Abstract

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We present an algorithm for calculating the geometric intersection number of two multicurves on the $n$-punctured disk, taking as input their Dynnikov coordinates. The algorithm has complexity $O(m^{2}n^{4})$, where $m$ is the sum of the absolute values of the Dynnikov coordinates of the two multicurves. The main ingredient is an algorithm due to Cumplido for relaxing a multicurve.

Type
Research Article
Copyright
© 2018 Australian Mathematical Publishing Association Inc. 

References

Artin, E., ‘Theory of braids’, Ann. of Math. (2) 48 (1947), 101126.Google Scholar
Bell, M. and Webb, R., ‘Applications of fast triangulation simplification’, Preprint, 2016, arXiv:1605.03514.Google Scholar
Birman, J. S., Braids, Links, and Mapping Class Groups, Annals of Mathematics Studies, 82 (Princeton University Press, Princeton, NJ, 1974).Google Scholar
Cumplido, M., ‘On the minimal positive standardizer of a parabolic subgroup of an Artin–Tits group’, Preprint, 2017, arXiv:1708.09310.Google Scholar
Dehornoy, P., Dynnikov, I., Rolfsen, D. and Wiest, B., Ordering Braids, Mathematical Surveys and Monographs, 148 (American Mathematical Society, Providence, RI, 2008).Google Scholar
Dynnikov, I., ‘On a Yang-Baxter mapping and the Dehornoy ordering’, Uspekhi Mat. Nauk 57(3(345)) (2002), 151152.Google Scholar
Hall, T. and Yurttaş, S. Ö., ‘On the topological entropy of families of braids’, Topol. Appl. 156(8) (2009), 15541564.CrossRefGoogle Scholar
Moussafir, J.-O., ‘On computing the entropy of braids’, Funct. Anal. Other Math. 1(1) (2006), 3746.Google Scholar
Schaefer, M., Sedgwick, E. and Štefankovič, D., ‘Computing Dehn twists and geometric intersection numbers in polynomial time’, in: Proceedings of the 20th Canadian Conference on Computational Geometry (CCCG2008) (2008), 111114.Google Scholar
Yurttaş, S. Ö., ‘Geometric intersection of curves on punctured disks’, J. Math. Soc. Japan 65(4) (2013), 11531168.Google Scholar