English

Positive scalar curvature and exotic structures on simply connected four manifolds

Differential Geometry 2025-01-28 v2 Geometric Topology

Abstract

We address Gromov's band width inequality and Rosenberg's S1S^1-stability conjecture for simply connected smooth four manifolds. Both results are known to be false in dimension 4 due to counterexamples based on Seiberg-Witten invariants. Nevertheless we show that both of these results hold upon considering simply connected smooth four manifolds up to homeomorphism. We also obtain a related result for non-simply connected smooth four manifolds.

Keywords

Cite

@article{arxiv.2501.01113,
  title  = {Positive scalar curvature and exotic structures on simply connected four manifolds},
  author = {Aditya Kumar and Balarka Sen},
  journal= {arXiv preprint arXiv:2501.01113},
  year   = {2025}
}

Comments

v2. 19 pages. Substantially revised: Corrected lemmas and significantly simplified proofs in Section 3, added a new result for non-simply connected 4-manifolds. Minor improvements in exposition