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Image Milnor number and đť’śe-codimension for maps between weighted homogeneous irreducible curves

  • D. A. H. Ament , J. J. Nuño-Ballesteros and J. N. Tomazella EMAIL logo
Published/Copyright: June 22, 2019
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Abstract

Let (X, 0) ⊂ (ℂn, 0) be an irreducible weighted homogeneous singularity curve and let f : (X, 0) → (ℂ2, 0) be a finite map germ, one-to-one and weighted homogeneous with the same weights of (X, 0). We show that 𝒜e-codim(X, f) = μI(f), where the 𝒜e-codimension 𝒜e-codim(X, f) is the minimum number of parameters in a versal deformation and μI(f) is the image Milnor number, i.e. the number of vanishing cycles in the image of a stabilization of f.

  1. Communicated by: R. Cavalieri

  2. Funding: The first author has been supported by CAPES. The second author has been partially supported by DGICYT Grant MTM2015–64013–P. The third author is partially supported by CNPq Grant 309086/2017-5 and FAPESP Grant 2016/04740-7.

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Received: 2017-11-01
Revised: 2018-06-12
Published Online: 2019-06-22
Published in Print: 2020-07-28

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