{"title":"单连通域上Banach空间的Bohr半径","authors":"Vasudevarao Allu, Himadri Halder","doi":"10.1017/s0013091523000688","DOIUrl":null,"url":null,"abstract":"Abstract 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 Ω containing the unit disk $\\mathbb{D}:=\\{z\\in \\mathbb{C}:|z| \\lt 1\\}$ into a complex Banach space X with $\\left\\lVert f\\right\\rVert_{H^{\\infty}(\\Omega,X)} \\leq 1$ . Let $\\phi=\\{\\phi_{n}(r)\\}_{n=0}^{\\infty}$ with $\\phi_{0}(r)\\leq 1$ such that $\\sum_{n=0}^{\\infty} \\phi_{n}(r)$ converges locally uniformly with respect to $r \\in [0,1)$ . For $1\\leq p,q \\lt \\infty$ , we denote \\begin{equation*} R_{p,q,\\phi}(f,\\Omega,X)= \\sup \\left\\{r \\geq 0: \\left\\lVert x_{0}\\right\\rVert^p \\phi_{0}(r) + \\left(\\sum_{n=1}^{\\infty} \\left\\lVert x_{n}\\right\\rVert\\phi_{n}(r)\\right)^q \\leq \\phi_{0}(r)\\right\\} \\end{equation*} and define the Bohr radius associated with ϕ by \\begin{equation*}R_{p,q,\\phi}(\\Omega,X)=\\inf \\left\\{R_{p,q,\\phi}(f,\\Omega,X): \\left\\lVert f\\right\\rVert_{H^{\\infty}(\\Omega,X)} \\leq 1\\right\\}.\\end{equation*} In this article, we extensively study the Bohr radius $R_{p,q,\\phi}(\\Omega,X)$ , when X is an arbitrary Banach space, and $X=\\mathcal{B}(\\mathcal{H})$ is the algebra of all bounded linear operators on a complex Hilbert space $\\mathcal{H}$ . Furthermore, we establish the Bohr inequality for the operator-valued Cesáro operator and Bernardi operator.","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":"237 6","pages":"0"},"PeriodicalIF":0.7000,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Bohr Radius for Banach Spaces on Simply Connected Domains\",\"authors\":\"Vasudevarao Allu, Himadri Halder\",\"doi\":\"10.1017/s0013091523000688\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Abstract 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 Ω containing the unit disk $\\\\mathbb{D}:=\\\\{z\\\\in \\\\mathbb{C}:|z| \\\\lt 1\\\\}$ into a complex Banach space X with $\\\\left\\\\lVert f\\\\right\\\\rVert_{H^{\\\\infty}(\\\\Omega,X)} \\\\leq 1$ . Let $\\\\phi=\\\\{\\\\phi_{n}(r)\\\\}_{n=0}^{\\\\infty}$ with $\\\\phi_{0}(r)\\\\leq 1$ such that $\\\\sum_{n=0}^{\\\\infty} \\\\phi_{n}(r)$ converges locally uniformly with respect to $r \\\\in [0,1)$ . For $1\\\\leq p,q \\\\lt \\\\infty$ , we denote \\\\begin{equation*} R_{p,q,\\\\phi}(f,\\\\Omega,X)= \\\\sup \\\\left\\\\{r \\\\geq 0: \\\\left\\\\lVert x_{0}\\\\right\\\\rVert^p \\\\phi_{0}(r) + \\\\left(\\\\sum_{n=1}^{\\\\infty} \\\\left\\\\lVert x_{n}\\\\right\\\\rVert\\\\phi_{n}(r)\\\\right)^q \\\\leq \\\\phi_{0}(r)\\\\right\\\\} \\\\end{equation*} and define the Bohr radius associated with ϕ by \\\\begin{equation*}R_{p,q,\\\\phi}(\\\\Omega,X)=\\\\inf \\\\left\\\\{R_{p,q,\\\\phi}(f,\\\\Omega,X): \\\\left\\\\lVert f\\\\right\\\\rVert_{H^{\\\\infty}(\\\\Omega,X)} \\\\leq 1\\\\right\\\\}.\\\\end{equation*} In this article, we extensively study the Bohr radius $R_{p,q,\\\\phi}(\\\\Omega,X)$ , when X is an arbitrary Banach space, and $X=\\\\mathcal{B}(\\\\mathcal{H})$ is the algebra of all bounded linear operators on a complex Hilbert space $\\\\mathcal{H}$ . Furthermore, we establish the Bohr inequality for the operator-valued Cesáro operator and Bernardi operator.\",\"PeriodicalId\":20586,\"journal\":{\"name\":\"Proceedings of the Edinburgh Mathematical Society\",\"volume\":\"237 6\",\"pages\":\"0\"},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2023-11-03\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Proceedings of the Edinburgh Mathematical Society\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1017/s0013091523000688\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Edinburgh Mathematical Society","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1017/s0013091523000688","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Bohr Radius for Banach Spaces on Simply Connected Domains
Abstract 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 Ω containing the unit disk $\mathbb{D}:=\{z\in \mathbb{C}:|z| \lt 1\}$ into a complex Banach space X with $\left\lVert f\right\rVert_{H^{\infty}(\Omega,X)} \leq 1$ . Let $\phi=\{\phi_{n}(r)\}_{n=0}^{\infty}$ with $\phi_{0}(r)\leq 1$ such that $\sum_{n=0}^{\infty} \phi_{n}(r)$ converges locally uniformly with respect to $r \in [0,1)$ . For $1\leq p,q \lt \infty$ , we denote \begin{equation*} R_{p,q,\phi}(f,\Omega,X)= \sup \left\{r \geq 0: \left\lVert x_{0}\right\rVert^p \phi_{0}(r) + \left(\sum_{n=1}^{\infty} \left\lVert x_{n}\right\rVert\phi_{n}(r)\right)^q \leq \phi_{0}(r)\right\} \end{equation*} and define the Bohr radius associated with ϕ by \begin{equation*}R_{p,q,\phi}(\Omega,X)=\inf \left\{R_{p,q,\phi}(f,\Omega,X): \left\lVert f\right\rVert_{H^{\infty}(\Omega,X)} \leq 1\right\}.\end{equation*} In this article, we extensively study the Bohr radius $R_{p,q,\phi}(\Omega,X)$ , when X is an arbitrary Banach space, and $X=\mathcal{B}(\mathcal{H})$ is the algebra of all bounded linear operators on a complex Hilbert space $\mathcal{H}$ . Furthermore, we establish the Bohr inequality for the operator-valued Cesáro operator and Bernardi operator.
期刊介绍:
The Edinburgh Mathematical Society was founded in 1883 and over the years, has evolved into the principal society for the promotion of mathematics research in Scotland. The Society has published its Proceedings since 1884. This journal contains research papers on topics in a broad range of pure and applied mathematics, together with a number of topical book reviews.