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Related papers: Mixed Bohr radius in several variables

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The main aim of this article is to establish a sharp improvement of the classical Bohr inequality for bounded holomorphic mappings in the polydisk $\mathbb{P}\Delta(0;1_n)$. We also prove two other sharp versions of the Bohr inequality in…

Complex Variables · Mathematics 2025-12-09 Molla Basir Ahamed , Sujoy Majumder , Nabadwip Sarkar , Ming-Sheng Liu

Let $H^{\infty}(\Omega,X)$ be the space of bounded analytic functions $f(z)=\sum_{n=0}^{\infty} x_{n}z^{n}$ from a proper simply connected domain $\Omega$ containing the unit disk $\mathbb{D}:=\{z\in \mathbb{C}:|z|<1\}$ into a complex…

Complex Variables · Mathematics 2026-04-15 Vasudevarao Allu , Himadri Halder

This paper is devoted to the investigation of multidimensional analogues of refined Bohr-type inequalities for bounded holomorphic mappings on the unit polydisc $\mathbb{D}^n$. We establish a sharp extension of the classical Bohr…

Complex Variables · Mathematics 2026-01-13 Molla Basir Ahamed , Sujoy Majumder , Nabadwip Sarkar

The Bohr radius for an arbitrary class $\mathcal{F}$ of analytic functions of the form $f(z)=\sum_{n=0}^{\infty}a_nz^n$ on the unit disk $\mathbb{D}=\{z\in\mathbb{C} : |z|<1\}$ is the largest radius $R_{\mathcal{F}}$ such that every…

Complex Variables · Mathematics 2024-08-28 Molla Basir Ahamed , Partha Pratim Roy

We consider the Bohr radius $R_n$ for the class of complex polynomials in one variable of degree at most $n$. It was conjectured by R. Fournier in 2008 that $R_n={1\over 3}+{\pi^2\over {3n^2}}+o({1\over n^2})$. We shall prove this…

Complex Variables · Mathematics 2014-04-07 Cheng Chu

This paper mainly uses the nonnegative continuous function $\{\zeta_n(r)\}_{n=0}^{\infty}$ to redefine the Bohr radius for the class of analytic functions satisfying $\real f(z)<1$ in the unit disk $|z|<1$ and redefine the Bohr radius of…

Complex Variables · Mathematics 2021-06-22 Rou-Yuan Lin , Ming-Sheng Liu , Saminathan Ponnusamy

For any complex Banach space $X$ and each $p \in [1,\infty)$, we introduce the $p$-Bohr radius of order $N(\in \mathbb{N})$ is $\widetilde{R}_{p,N}(X)$ defined by $$ \widetilde{R}_{p,N}(X)=\sup \left\{r\geq 0: \sum_{k=0}^{N}\norm{x_k}^p…

Functional Analysis · Mathematics 2026-04-15 Vasudevarao Allu , Himadri Halder , Subhadip Pal

Let $ \mathcal{H}(\mathbb{D}) $ be the class of analytic functions in the unit disk $ \mathbb{D} : =\{z\in\mathbb{C} : |z|<1\} $. The classical Bohr's inequality states that if a power series $ f(z)=\sum_{n=0}^{\infty}a_nz^n $ converges in…

Complex Variables · Mathematics 2020-12-14 Molla Basir Ahamed , Vasudevarao Allu , Himadri Halder

The classical Bohr inequality states that if $ f $ is an analytic function with the power series representation $ f(z)=\sum_{n=0}^{\infty}a_nz^n $ in the unit disk $ \mathbb{D}:=\{z\in\mathbb{C} : |z|<1\} $ such that $ |f(z)|\leq 1 $ for…

Complex Variables · Mathematics 2021-04-12 Molla Basir Ahamed , Vasudevarao Allu

Let $ \mathcal{H}(\Omega) $ be the class of complex-valued functions harmonic in $ \Omega\subset\mathbb{C} $ and each $f=h+\overline{g}\in \mathcal{H}(\Omega)$, where $ h $ and $ g $ are analytic. In the study of Bohr phenomenon for certain…

Complex Variables · Mathematics 2024-02-20 Molla Basir Ahamed , Partha Pratim Roy

The main aim of this article is to establish a sharp improvement of the classical Bohr inequality for bounded holomorphic mappings in the polydisk $\mathbb{D}^n$.We also prove two other sharp versions of the Bohr inequality in the setting…

Complex Variables · Mathematics 2025-12-19 Molla Basir Ahamed , Sujoy Majumder , Nabadwip Sarkar

The Bohnenblust--Hille inequality says that the $\ell^{\frac{2m}{m+1}}$-norm of the coefficients of an $m$-homogeneous polynomial $P$ on $\C^n$ is bounded by $\| P\|_\infty$ times a constant independent of $n$, where $\|\cdot \|_\infty$…

Complex Variables · Mathematics 2011-10-06 Andreas Defant , Leonhard Frerick , Joaquim Ortega-Cerdà , Myriam Ounaïes , Kristian Seip

In this paper, we investigates the Bohr phenomenon for holomorphic mappings $F$ from the unit ball $\mathbb{B}_X$ of a complex Banach space $X$ into the closure of the unit polydisc $\mathbb{D}^m$ within the space $\mathbb{C}^m$. First, we…

Complex Variables · Mathematics 2025-11-25 Vasudevarao Allu , Raju Biswas , Rajib Mandal

We study the asymptotic decay of the Fourier spectrum of real functions $f\colon \{-1,1\}^N \rightarrow \mathbb{R}$ in the spirit of Bohr's phenomenon from complex analysis. Every such function admits a canonical representation through its…

Functional Analysis · Mathematics 2017-07-31 Andreas Defant , Mieczysław Mastyło , Antonio Pérez

We say that a class $\mathcal{B}$ of analytic functions $f$ of the form $f(z)=\sum_{n=0}^{\infty} a_{n}z^{n}$ in the unit disk $\mathbb{D}:=\{z\in \mathbb{C}: |z|<1\}$ satisfies a Bohr phenomenon if for the largest radius $R_{f}<1$, the…

Complex Variables · Mathematics 2026-04-15 Vasudevarao Allu , Himadri Halder

Let $ \mathcal{H}(\mathbb{D}) $ be the linear space of analytic functions on the unit disk $ \mathbb{D}=\{z\in\mathbb{C}: |z|<1\} $ and let $ \mathcal{B}=\{w\in \mathcal{H}(\mathbb{D}: |w(z)|<1)\} $. The classical Bohr's inequality states…

Complex Variables · Mathematics 2021-03-16 Molla Basir Ahamed , Vasudevarao Allu

This article introduces the notion of arithmetic Bohr radius for operator valued pluriharmonic functions on complete Reinhardt domains in $\mathbb{C}^n$. Using tools from local Banach space theory, we determine its asymptotic behavior in…

Complex Variables · Mathematics 2026-02-19 Himadri Halder

In this paper, we introduce the notion of the second Bohr radius for vector valued pluriharmonic functions on complete Reinhardt domains in $\mathbb{C}^n$. This investigation is motivated by the work of Lev Aizenberg [Proc. Amer. Math. Soc.…

Complex Variables · Mathematics 2026-03-03 Himadri Halder

We prove that the Bohr' radius for large functions is $e^{-\pi }.$

Complex Variables · Mathematics 2020-10-15 Loai Shakaa , Yusuf Abu Muhanna

In this paper, we first obtain a refined Bohr radius for invariant families of bounded analytic functions on unit disk $ \mathbb{D} $. Then, we obtain Bohr inequality for certain integral transforms, namely Fourier (discrete) and Laplace…

Complex Variables · Mathematics 2024-05-08 Molla Basir Ahamed , Partha Pratim Roy , Sabir Ahammed