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arXiv · 0808.0158

Approximate Roots, Toric Resolutions and Deformations of a Plane Branch

Pedro Daniel Gonzalez Perez
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Abstract

We analyze the expansions in terms of the approximate roots of a Weierstrass polynomial $f$ defining a plane branch $(C,0)$, in the light of the toric embedded resolution of the branch. This leads to the definition of a class of (non equisingular) deformations of a plane branch $(C,0)$ supported on certain monomials in the approximate roots of $f$. As a consequence we find out a Kouchnirenko type formula for the Milnor number $(C,0)$. Our results provide a geometrical approach to Abhyankar's straight line conditions and its consequences. As an application we give an equisingularity criterion for a family of plane curves to be equisingular to a plane branch and we express it algorithmically.

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Pedro Daniel Gonzalez Perez. 2008-08-01. Approximate Roots, Toric Resolutions and Deformations of a Plane Branch. https://arxiv.org/abs/0808.0158

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