Profinite almost rigidity in 3-manifolds
We prove that any compact, orientable 3-manifold with empty or toral boundary is profinitely almost rigid among all compact, orientable 3-manifolds. In other words, the profinite completion of its fundamental group determines its homeomorphism type to finitely many possibilities. Moreover, the profinite completion of the fundamental group of a mixed 3-manifold together with the peripheral structure uniquely determines the homeomorphism type of its Seifert part, i.e. the maximal graph manifold components in the JSJ-decomposition. On the other hand, without assigning the peripheral structure, the profinite completion of a mixed 3-manifold group may not uniquely determine the fundamental group of its Seifert part. The proof is based on JSJ-decomposition.
Authors
- Xiaoyu Xu (ORCID: https://orcid.org/0000-0003-2185-6724)
Institutions
- Peking University (CN)
- Peking University International Hospital (CN)
Publication Details
- Journal
- Advances in Mathematics
- Published
- 2025-09-02
- DOI
- https://doi.org/10.1016/j.aim.2025.110505
- Primary Topic
- Geometric and Algebraic Topology
- Type
- article
- Field-Weighted Citation Impact
- 0.00