English

Weights of circle actions on oriented manifolds with isolated fixed points

Algebraic Topology 2026-05-05 v1

Abstract

For an action of the circle group S1S^1 on a compact oriented manifold with isolated fixed points, there is a claim that weights at the fixed points occur in pairs. This phenomenon holds for other types of S1S^1-manifolds, e.g., (almost) complex, symplectic, and unitary manifolds. A known proof of this claim assumes that the isotropy submanifolds are orientable. However, this assumption does not hold in general. In this note, we prove the claim without relying on that assumption.

Keywords

Cite

@article{arxiv.2605.01722,
  title  = {Weights of circle actions on oriented manifolds with isolated fixed points},
  author = {Donghoon Jang},
  journal= {arXiv preprint arXiv:2605.01722},
  year   = {2026}
}
R2 v1 2026-07-01T12:47:13.304Z