{"title":"Numerical radius in Hilbert C✻-modules","authors":"A. Zamani","doi":"10.7153/mia-2021-24-71","DOIUrl":null,"url":null,"abstract":". Utilizing the linking algebra of a Hilbert C ∗ -module (cid:2) V , (cid:3)·(cid:3) (cid:3) , we introduce Ω ( x ) as a de fi nition of numerical radius for an element x ∈ V and then show that Ω ( · ) is a norm on V such that 12 (cid:3) x (cid:3) (cid:2) Ω ( x ) (cid:2) (cid:3) x (cid:3) . In addition, we obtain an equivalent condition for Ω ( x ) = 12 (cid:3) x (cid:3) . Moreover, we present a re fi nement of the triangle inequality for the norm Ω ( · ) . Some other related results are also discussed.","PeriodicalId":49868,"journal":{"name":"Mathematical Inequalities & Applications","volume":"1 1","pages":""},"PeriodicalIF":0.9000,"publicationDate":"2021-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mathematical Inequalities & Applications","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.7153/mia-2021-24-71","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 4
Abstract
. Utilizing the linking algebra of a Hilbert C ∗ -module (cid:2) V , (cid:3)·(cid:3) (cid:3) , we introduce Ω ( x ) as a de fi nition of numerical radius for an element x ∈ V and then show that Ω ( · ) is a norm on V such that 12 (cid:3) x (cid:3) (cid:2) Ω ( x ) (cid:2) (cid:3) x (cid:3) . In addition, we obtain an equivalent condition for Ω ( x ) = 12 (cid:3) x (cid:3) . Moreover, we present a re fi nement of the triangle inequality for the norm Ω ( · ) . Some other related results are also discussed.
期刊介绍:
''Mathematical Inequalities & Applications'' (''MIA'') brings together original research papers in all areas of mathematics, provided they are concerned with inequalities or their role. From time to time ''MIA'' will publish invited survey articles. Short notes with interesting results or open problems will also be accepted. ''MIA'' is published quarterly, in January, April, July, and October.