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Decompositions of the higher order polars of plane branches

  • Evelia R. García Barroso EMAIL logo and Janusz Gwoździewicz
Published/Copyright: June 15, 2016

Abstract

In [1] Casas-Alvero found decompositions of higher order polars of an irreducible plane complex analytic curve generalizing the results of Merle. We improve his result obtaining a finer decomposition where we find out a kind of branches that we call threshold semi-roots. The existence of threshold semi-roots is a new phenomenon observed for the higher order polars. The topological type and the number of these branches is determined by the topological type of the original curve.

MSC 2010: 32S05; 32S99

Communicated by Junjiro Noguchi


Award Identifier / Grant number: MTM2012-36917-C03-01

Funding statement: The first-named author was partially supported by the Spanish Project MTM2012-36917-C03-01 and the second author was partially supported by the Plan Propio de Investigación de la Universidad de La Laguna-2014.

Acknowledgements

The authors thank Bernard Teissier for suggesting the name threshold semi-root.

References

[1] Casas-Alvero E., Higher order polar germs, J. Algebra 240 (2001), 326–337. 10.1006/jabr.2000.8727Search in Google Scholar

[2] García Barroso E. R., Gwoździewicz J. and Lenarcik A., Non-degeneracy of the discriminant, Acta Math. Hungar. 147 (2015), no. 1, 220–246. 10.1007/s10474-015-0515-8Search in Google Scholar

[3] García Barroso E. R. and Teissier B., Concentration multi-échelles de courbure dans des fibres de Milnor, Comment. Math. Helv. 74 (1999), 398–418. 10.1007/s000140050096Search in Google Scholar

[4] Gwoździewicz J., Ephraim’s pencils, Int. Math. Res. Not. IMRN 2013 (2013), no. 15, 3371–3385. 10.1093/imrn/rns148Search in Google Scholar

[5] Hefez A., Irreducible plane curve singularities, Real and Complex Singularities (Saõ Carlos 2000), Lecture Notes Pure Appl. Math. 232, Marcel Dekker, New York (2003), 1–120. 10.1201/9780203912089-1Search in Google Scholar

[6] Koike S. and Parusiński A., Equivalence relations for two variable real analytic function germs, J. Math. Soc. Japan 65 (2013), no. 1, 237–276. 10.2969/jmsj/06510237Search in Google Scholar

[7] Lê D. T., Michel F. and Weber C., Sur le comportement des polaires associées aux germes de courbes planes, Compos. Math. 72 (1989), 87–113. Search in Google Scholar

[8] Merle M., Invariants polaires des courbes planes, Invent. Math. 41 (1977), 103–111. 10.1007/BF01418370Search in Google Scholar

[9] Pham F., Déformations equisingulières des idéaux Jacobiens de courbes planes, Proceedings of Liverpool Singularities Symposium II, Lecture Notes in Math. 209, Springer, Berlin (1971), 218–233. 10.1007/BFb0068907Search in Google Scholar

Received: 2016-2-22
Revised: 2016-4-3
Published Online: 2016-6-15
Published in Print: 2017-3-1

© 2017 by De Gruyter

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