English

The Bohr inequality on a simply connected domain and its applications

Complex Variables 2024-05-06 v1

Abstract

In this article, we first establish a generalized Bohr inequality and examine its sharpness for a class of analytic functions ff in a simply connected domain Ωγ,\Omega_\gamma, where 0γ<10\leq \gamma<1 with a sequence {φn(r)}n=0\{\varphi_n(r) \}^{\infty}_{n=0} of non-negative continuous functions defined on [0,1)[0,1) such that the series n=0φn(r)\sum_{n=0}^{\infty}\varphi_n(r) converges locally uniformly on [0,1)[0,1). Our results represent twofold generalizations corresponding to those obtained for the classes B(D)\mathcal{B}(\mathbb{D}) and B(Ωγ)\mathcal{B}(\Omega_{\gamma}), where \begin{align*} \Omega_{\gamma}:=\biggl\{z\in \mathbb{C}: \bigg|z+\dfrac{\gamma}{1-\gamma}\bigg|<\dfrac{1}{1-\gamma}\biggr\}. \end{align*} As a convolution counterpart, we determine the Bohr radius for hypergeometric function on Ωγ \Omega_{\gamma} . Lastly, we establish a generalized Bohr inequality and its sharpness for the class of K K -quasiconformal, sense-preserving harmonic maps of the form f=h+gf=h+\overline{g} in Ωγ.\Omega_{\gamma}.

Keywords

Cite

@article{arxiv.2405.01895,
  title  = {The Bohr inequality on a simply connected domain and its applications},
  author = {Sabir Ahammed and Molla Basir Ahamed and Partha Pratim Roy},
  journal= {arXiv preprint arXiv:2405.01895},
  year   = {2024}
}