English

$PD_3$-complexes bound

Geometric Topology 2023-01-18 v5

Abstract

We show that every PD3PD_3-complex PP bounds a PD4PD_4-pair (Z,P)(Z,P). If PP is orientable we may assume that π1(Z)=1\pi_1(Z)=1. We show also that if PP has a manifold 1-skeleton then it is homotopy equivalent to a closed 3-manifold, and that if the inclusion of ZZ into PP induces an isomorphism on fundamental groups then π1(Z)\pi_1(Z) is a free group.

Keywords

Cite

@article{arxiv.2109.09947,
  title  = {$PD_3$-complexes bound},
  author = {Jonathan A. Hillman},
  journal= {arXiv preprint arXiv:2109.09947},
  year   = {2023}
}

Comments

v2: Proof of Theorem 1 elaborated. New Theorem 2, on $PD_3$-complexes with manifold 1-skeleta; the original \S3 now an appendix. v3: new section, extending a theorem of Daverman to the $PD_4$-context. v4: appendix deleted, \S4 moved to follow \S1. Other minor changes. v5: exposition of Theorem 1, Lemma 3 and Theorem 4 tightened