首页    期刊浏览 2022年07月07日 星期四
登录注册

文章基本信息

  • 标题:Spatial numerical ranges of elements of Banach algebras
  • 本地全文:下载
  • 作者:A. K. Gaur ; T. Husain
  • 期刊名称:International Journal of Mathematics and Mathematical Sciences
  • 印刷版ISSN:0161-1712
  • 电子版ISSN:1687-0425
  • 出版年度:1989
  • 卷号:12
  • DOI:10.1155/S0161171289000785
  • 出版社:Hindawi Publishing Corporation
  • 摘要:In this paper, the notion of spatial numerical range of elements of Banach algebras without identity is studied. Specifically, the relationship between spatial numerical ranges, numerical ranges and spectra is investigated. Among other results, it is shown that the closure of the spatial numerical range of an element of a Banach algebra without Identity but wlth regular norm is exactly its numerical range as an element of the unitized algebra. Futhermore, the closure of the spatial numerical range of a hermitian element coincides with the convex hull of its spectrum. In particular, spatial numerical ranges of the elements of the Banach algebra C0(X) are described.
国家哲学社会科学文献中心版权所有