English

Non-smoothable surfaces in the 4-sphere

Geometric Topology 2026-05-22 v2

Abstract

We construct examples of non-smoothable surfaces in the 44-sphere, thereby answering Question 4.32 on the K3 problem list. These surfaces are non-orientable and have knot group of order 22, thus simultaneously answering Question 4.29(a) on the K3 problem list.

Keywords

Cite

@article{arxiv.2603.22202,
  title  = {Non-smoothable surfaces in the 4-sphere},
  author = {Anthony Conway and Daniel Galvin},
  journal= {arXiv preprint arXiv:2603.22202},
  year   = {2026}
}

Comments

v1: 17 pages. v2: Reorganisation of the introduction. Weakened Theorem 1.2 to account for an oversight in the proof; see the new Proposition 5.4. The advertised main theorem remains unchanged. 22 pages. 2 Figures

R2 v1 2026-07-01T11:33:41.276Z