{"title":"On Operator Valued Haar Unitaries and Bipolar Decompositions of R-diagonal Elements","authors":"","doi":"10.1007/s00020-024-02760-z","DOIUrl":null,"url":null,"abstract":"<h3>Abstract</h3> <p>In the context of operator valued W<span> <span>\\(^*\\)</span> </span>-free probability theory, we study Haar unitaries, R-diagonal elements and circular elements. Several classes of Haar unitaries are differentiated from each other. The term bipolar decomposition is used for the expression of an element as <em>vx</em> where <em>x</em> is self-adjoint and <em>v</em> is a partial isometry, and we study such decompositions of operator valued R-diagonal and circular elements that are free, meaning that <em>v</em> and <em>x</em> are <span> <span>\\(*\\)</span> </span>-free from each other. In particular, we prove, when <span> <span>\\(B={\\textbf{C}}^2\\)</span> </span>, that if a <em>B</em>-valued circular element has a free bipolar decomposition with <em>v</em> unitary, then it has one where <em>v</em> normalizes <em>B</em>.</p>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00020-024-02760-z","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
In the context of operator valued W\(^*\)-free probability theory, we study Haar unitaries, R-diagonal elements and circular elements. Several classes of Haar unitaries are differentiated from each other. The term bipolar decomposition is used for the expression of an element as vx where x is self-adjoint and v is a partial isometry, and we study such decompositions of operator valued R-diagonal and circular elements that are free, meaning that v and x are \(*\)-free from each other. In particular, we prove, when \(B={\textbf{C}}^2\), that if a B-valued circular element has a free bipolar decomposition with v unitary, then it has one where v normalizes B.
摘要 在无算子值 W (^*\)概率论的背景下,我们研究了哈尔单元、R 对角元素和圆元素。我们将几类 Haar 单元相互区分开来。双极分解这一术语用于表达一个元素为 vx,其中 x 是自共轭的,v 是部分等距的,我们研究了算子值 R 对角元素和圆元素的这种分解,它们是自由的,这意味着 v 和 x 彼此是 \(*\) -free 的。特别是,我们证明,当 \(B={\textbf{C}}^2\) 时,如果一个 B 值圆周元素有一个自由的双极分解,且 v 是单元的,那么它就有一个 v 使 B 正常化的双极分解。