English

Characterizing meromorphic pseudo-lemniscates

Complex Variables 2020-01-14 v1

Abstract

Let ff be a meromorphic function with simply connected domain GCG\subset\mathbb{C}, and let ΓC\Gamma\subset\mathbb{C} be a smooth Jordan curve. We call a component of f1(Γ)f^{-1}(\Gamma) in GG a Γ\Gamma-pseudopseudo-lemniscatelemniscate of ff. In this note we give criteria for a smooth Jordan curve S\mathcal{S} in GG (with bounded face DD) to be a psuedo-lemniscate of ff in terms of the number of preimages (counted with multiplicity) which a given ww has under ff in DD, as ww ranges over the Riemann sphere. We also develop a test, in the same terms, by which one may show that the image of a Jordan curve under ff is not a Jordan curve.

Keywords

Cite

@article{arxiv.1607.04607,
  title  = {Characterizing meromorphic pseudo-lemniscates},
  author = {Trevor Richards},
  journal= {arXiv preprint arXiv:1607.04607},
  year   = {2020}
}

Comments

7 pages, Follow-up to "Conformal Models and Fingerprints of Pseudo-lemniscates" by Richards and Younsi

R2 v1 2026-06-22T14:56:00.136Z