English

Bohr radius for locally univalent harmonic mappings

Complex Variables 2017-09-15 v1

Abstract

We consider the class of all sense-preserving harmonic mappings f=h+gf= h+\overline{g} of the unit disk \ID\ID, where hh and gg are analytic with g(0)=0g(0)=0, and determine the Bohr radius if any one of the following conditions holds: \bee hh is bounded in \ID\ID. hh satisfies the condition Reh(z)1{\rm Re}\, h(z)\leq 1 in D\mathbb{D} with h(0)>0h(0)>0. both hh and gg are bounded in \ID\ID. hh is bounded and g(0)=0g'(0)=0. \eee We also consider the problem of determining the Bohr radius when the supremum of the modulus of the dilatation of ff in \ID\ID is strictly less than 11. In addition, we determine the Bohr radius for the space B\mathcal B of analytic Bloch functions and the space BH{\mathcal B}_H of harmonic Bloch functions. The paper concludes with two conjectures.

Keywords

Cite

@article{arxiv.1709.04629,
  title  = {Bohr radius for locally univalent harmonic mappings},
  author = {Ilgiz R Kayumov and Saminathan Ponnusamy and Nail Shakirov},
  journal= {arXiv preprint arXiv:1709.04629},
  year   = {2017}
}

Comments

13 pages; The article will appear in Mathematische Nachrichten

R2 v1 2026-06-22T21:42:44.553Z