English

Harmonic diffeomorphisms between pseudo-riemannian surfaces

Differential Geometry 2023-09-25 v2

Abstract

We study locally harmonic maps between a Riemann surface or Lorentz surface MM and a Riemann surface or Lorentz surface NN. {All four cases are studied in a unified way}. All four cases are written using a unified formalism. Therefore solutions to the harmonic map problem can be studied in a unified way. Harmonic maps between pseudo-Riemannian surfaces are classified by the classification of the solutions of a generalized sine-Gordon equation. We then study the one-soliton solutions of this equation and we find the corresponding harmonic maps in a unified way. Next, we discuss a B\"acklund transformation of the harmonic map equations that provides a connection between the solutions of two sine-Gordon type equations. Finally, we give an example of a harmonic map that is constructed by the use of a B\"acklund transformation.

Keywords

Cite

@article{arxiv.2308.06625,
  title  = {Harmonic diffeomorphisms between pseudo-riemannian surfaces},
  author = {A. Fotiadis and C. Daskaloyannis},
  journal= {arXiv preprint arXiv:2308.06625},
  year   = {2023}
}
R2 v1 2026-06-28T11:54:23.705Z