English

Four-manifolds up to connected sum with complex projective planes

Geometric Topology 2023-04-13 v2 Algebraic Topology

Abstract

We show that closed, connected 4-manifolds up to connected sum with copies of the complex projective plane are classified in terms of the fundamental group, the orientation character and an extension class involving the second homotopy group. For fundamental groups that are torsion free or have one end, we reduce this further to a classification in terms of the homotopy 2-type.

Keywords

Cite

@article{arxiv.1802.09811,
  title  = {Four-manifolds up to connected sum with complex projective planes},
  author = {Daniel Kasprowski and Mark Powell and Peter Teichner},
  journal= {arXiv preprint arXiv:1802.09811},
  year   = {2023}
}

Comments

37 pages. v2: former sections 5 and 6 rewritten and split into current sections 5, 6, and 7. Accepted for publication in American Journal of Mathematics

R2 v1 2026-06-23T00:34:54.097Z