English

Lefschetz fibrations with infinitely many sections

Geometric Topology 2024-09-24 v1 Symplectic Geometry

Abstract

The Arakelov--Parshin rigidity theorem implies that a holomorphic Lefschetz fibration π:MS2\pi: M \to S^2 of genus g2g \geq 2 admits only finitely many holomorphic sections σ:S2M\sigma:S^2 \to M. We show that an analogous finiteness theorem does not hold for smooth or for symplectic Lefschetz fibrations. We prove a general criterion for a symplectic Lefschetz fibration to admit infinitely many homologically distinct sections and give many examples satisfying such assumptions. Furthermore, we provide examples that show that finiteness is not necessarily recovered by considering a coarser count of sections up to the action of the (smooth) automorphism group of a Lefschetz fibration.

Keywords

Cite

@article{arxiv.2409.15265,
  title  = {Lefschetz fibrations with infinitely many sections},
  author = {Seraphina Eun Bi Lee and Carlos A. Serván},
  journal= {arXiv preprint arXiv:2409.15265},
  year   = {2024}
}

Comments

21 pages, 8 figures

R2 v1 2026-06-28T18:54:05.496Z