English

Reversing orientation homeomorphisms of surfaces

Geometric Topology 2021-02-24 v1 Algebraic Topology

Abstract

Let MM be a connected compact orientable surface, f:MRf:M\to \mathbb{R} be a Morse function, and h:MMh:M\to M be a diffeomorphism which preserves ff in the sense that fh=ff\circ h = f. We will show that if hh leaves invariant each regular component of each level set of ff and reverses its orientation, then h2h^2 is isotopic to the identity map of MM via ff-preserving isotopy. This statement can be regarded as a foliated and a homotopy analogue of a well known observation that every reversing orientation orthogonal isomorphism of a plane has order 22, i.e. is a mirror symmetry with respect to some line. The obtained results hold in fact for a larger class of maps with isolated singularities from connected compact orientable surfaces to the real line and the circle.

Keywords

Cite

@article{arxiv.2102.11867,
  title  = {Reversing orientation homeomorphisms of surfaces},
  author = {Iryna Kuznietsova and Sergiy Maksymenko},
  journal= {arXiv preprint arXiv:2102.11867},
  year   = {2021}
}
R2 v1 2026-06-23T23:26:55.874Z