{"title":"Dynamics of Weighted Backward Shifts on Certain Analytic Function Spaces","authors":"Bibhash Kumar Das, Aneesh Mundayadan","doi":"10.1007/s00025-024-02279-0","DOIUrl":null,"url":null,"abstract":"<p>We introduce the Banach spaces <span>\\(\\ell ^p_{a,b}\\)</span> and <span>\\(c_{0,a,b}\\)</span>, of analytic functions on the unit disc, having normalized Schauder bases consisting of polynomials of the form <span>\\(f_n(z)=(a_n+b_nz)z^n, ~~n\\ge 0\\)</span>, where <span>\\(\\{f_n\\}\\)</span> is assumed to be equivalent to the standard basis in <span>\\(\\ell ^p\\)</span> and <span>\\(c_0\\)</span>, respectively. We study the weighted backward shift operator <span>\\(B_w\\)</span> on these spaces, and obtain necessary and sufficient conditions for <span>\\(B_w\\)</span> to be bounded, and prove that, under some mild assumptions on <span>\\(\\{a_n\\}\\)</span> and <span>\\(\\{b_n\\}\\)</span>, the operator <span>\\(B_w\\)</span> is similar to a compact perturbation of a weighted backward shift on the sequence spaces <span>\\(\\ell ^p\\)</span> or <span>\\(c_0\\)</span>. Further, we study the hypercyclicity, mixing, and chaos of <span>\\(B_w\\)</span>, and establish the existence of hypercyclic subspaces for <span>\\(B_w\\)</span> by computing its essential spectrum. Similar results are obtained for a function of <span>\\(B_w\\)</span> on <span>\\(\\ell ^p_{a,b}\\)</span> and <span>\\(c_{0,a,b}\\)</span>.</p>","PeriodicalId":54490,"journal":{"name":"Results in Mathematics","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Results in Mathematics","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00025-024-02279-0","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
We introduce the Banach spaces \(\ell ^p_{a,b}\) and \(c_{0,a,b}\), of analytic functions on the unit disc, having normalized Schauder bases consisting of polynomials of the form \(f_n(z)=(a_n+b_nz)z^n, ~~n\ge 0\), where \(\{f_n\}\) is assumed to be equivalent to the standard basis in \(\ell ^p\) and \(c_0\), respectively. We study the weighted backward shift operator \(B_w\) on these spaces, and obtain necessary and sufficient conditions for \(B_w\) to be bounded, and prove that, under some mild assumptions on \(\{a_n\}\) and \(\{b_n\}\), the operator \(B_w\) is similar to a compact perturbation of a weighted backward shift on the sequence spaces \(\ell ^p\) or \(c_0\). Further, we study the hypercyclicity, mixing, and chaos of \(B_w\), and establish the existence of hypercyclic subspaces for \(B_w\) by computing its essential spectrum. Similar results are obtained for a function of \(B_w\) on \(\ell ^p_{a,b}\) and \(c_{0,a,b}\).
期刊介绍:
Results in Mathematics (RM) publishes mainly research papers in all fields of pure and applied mathematics. In addition, it publishes summaries of any mathematical field and surveys of any mathematical subject provided they are designed to advance some recent mathematical development.