English

Retraction of the complement of smooth projective curves to a $2$-dimensional $\Delta$-complex

Algebraic Geometry 2026-05-27 v1 Algebraic Topology Combinatorics

Abstract

Due to a result by Andreotti and Frankel \cite{andreotti1959}, it can be seen that the complement of a complex projective curve has the homotopy type of a 22-dimensional CW complex. However, no general method has been given to compute explicitly this complex. Here we give a explicit construction of a 22- dimensional Δ\Delta-complex that is a strong deformation retract of the complement of a Fermat curve of degree dd in the complex projective space. The retraction is performed in several steps, using the branched cover structure of the Fermat curves over the degree 11 case.

Keywords

Cite

@article{arxiv.2605.26768,
  title  = {Retraction of the complement of smooth projective curves to a $2$-dimensional $\Delta$-complex},
  author = {E. Artal and A. Larraya Sancho and M. A. Marco Buzunariz},
  journal= {arXiv preprint arXiv:2605.26768},
  year   = {2026}
}