English

Topological and bilipschitz types of complex surface singularities and their links

Algebraic Geometry 2025-11-10 v2

Abstract

In this paper, we prove that two normal complex surface germs that are inner bilipschitz--but not necessarily orientation-preserving--homeomorphic, have in fact the same oriented topological type and the same minimal plumbing graph. Along the way, we show that the oriented homeomorphism type of an isolated complex surface singularity germ determines the oriented homeomorphism type of its link, providing a converse to the classical Conical Structure Theorem. These results require to study the topology first, and the inner lipschitz geometry later, of Hirzebruch-Jung and cusp singularities, the normal surface singularities whose links are lens spaces and fiber bundles over the circle.

Keywords

Cite

@article{arxiv.2501.03110,
  title  = {Topological and bilipschitz types of complex surface singularities and their links},
  author = {Lorenzo Fantini and Anne Pichon},
  journal= {arXiv preprint arXiv:2501.03110},
  year   = {2025}
}

Comments

v2: Exposition improved and minor modifications. 14 pages, 4 figures. To appear in Proceedings of the AMS