English

A note on spherical derivatives and normal families

Complex Variables 2010-10-25 v1

Abstract

We show that a family of meromorphic functions in the unit disk \dk\dk whose spherical derivatives are uniformly bounded away from zero is normal. Furthermore, we show that for each ff meromorphic in \dk\dk we have \inf_{z\in\dk} f^#(z)\le \frac{1}{2}where where f^#denotesthesphericalderivativeof denotes the spherical derivative of f$.

Keywords

Cite

@article{arxiv.1010.4654,
  title  = {A note on spherical derivatives and normal families},
  author = {Jürgen Grahl and Shahar Nevo},
  journal= {arXiv preprint arXiv:1010.4654},
  year   = {2010}
}

Comments

12 pages

R2 v1 2026-06-21T16:32:41.443Z