English

Injectivity of non-singular planar maps with disconnecting curves in the eigenvalues space

Classical Analysis and ODEs 2022-02-14 v1

Abstract

Fessler and Gutierrez \cite{Fe,Gu} proved that if a non-singular planar map has Jacobian matrix without eigenvalues in (0,+)(0,+\infty), then it is injective. We prove that the same holds replacing (0,+)(0,+\infty) with any unbounded curve disconnecting the upper (lower) complex half-plane. Additionally we prove that a Jacobian map (P,Q)(P,Q) is injective if Px+QyP_x + Q_y is not a surjective function.

Keywords

Cite

@article{arxiv.2202.05542,
  title  = {Injectivity of non-singular planar maps with disconnecting curves in the eigenvalues space},
  author = {Marco Sabatini},
  journal= {arXiv preprint arXiv:2202.05542},
  year   = {2022}
}