English

Lefschetz pencils on a complex projective plane from a topological viewpoint

Geometric Topology 2025-09-26 v1

Abstract

In this article, we present a differential topological construction of symplectic Lefschetz pencils of genus (d1)(d2)2\frac{(d-1)(d-2)}{2} with d2d^2 base points and 3(d1)23(d-1)^2 critical points for arbitrary d4d\geq 4, analogous to the holomorphic Lefschetz pencils of curves of degree dd in CP2\mathbb{C}P^2. Moreover, for the case d=4d=4, we derive an explicit monodromy factorization of the genus 33 holomorphic Lefschetz pencil on CP2\mathbb{C}P^2 based on the braid monodromy technique and prove that it can also be topologically constructed by breeding the monodromy relations of the genus 11 holomorphic Lefschetz pencils.

Keywords

Cite

@article{arxiv.2509.21069,
  title  = {Lefschetz pencils on a complex projective plane from a topological viewpoint},
  author = {Ju A Lee},
  journal= {arXiv preprint arXiv:2509.21069},
  year   = {2025}
}

Comments

29 pages, 23 Figures

R2 v1 2026-07-01T05:55:58.637Z