English

Constancy of the index for gradient mappings

Analysis of PDEs 2025-06-05 v1 Complex Variables Differential Geometry

Abstract

We show that if the Hessian of a C1,1C^{1,1} function has uniformly positive determinant almost everywhere then its index is locally constant, as conjectured by \v{S}ver\'ak in 1992. We deduce this result as a consequence of a more general theorem valid for quasiregular gradient mappings.

Cite

@article{arxiv.2506.03906,
  title  = {Constancy of the index for gradient mappings},
  author = {André Guerra and Riccardo Tione},
  journal= {arXiv preprint arXiv:2506.03906},
  year   = {2025}
}

Comments

16 pages

R2 v1 2026-07-01T02:58:57.004Z