## Banach Journal of Mathematical Analysis

### On the Cauchy-Schwarz inequality and its reverse in semi-inner product C*-modules

#### Abstract

There are many known Cauchy-Schwarz-type inequalities which are valid in different frameworks. In this paper we consider the $A$-valued Cauchy-Schwarz inequality and its reverse in a semi-inner product $A$-module over the $C^*$-algebra $A$. Some remarks on the $A$-valued Cauchy-Schwarz inequality in a semi-inner product $A$-module over the $H^*$-algebra $A$ are also given.

#### Article information

Source
Banach J. Math. Anal. Volume 1, Number 1 (2007), 78-84.

Dates
First available in Project Euclid: 21 April 2009

Permanent link to this document
https://projecteuclid.org/euclid.bjma/1240321557

Digital Object Identifier
doi:10.15352/bjma/1240321557

Mathematical Reviews number (MathSciNet)
MR2350196

Zentralblatt MATH identifier
1134.46036

Subjects
Primary: 46L08: $C^*$-modules
Secondary: 26D07: Inequalities involving other types of functions

#### Citation

Ilisevic, Dijana; Varosanec, Sanja. On the Cauchy-Schwarz inequality and its reverse in semi-inner product C*-modules. Banach J. Math. Anal. 1 (2007), no. 1, 78--84. doi:10.15352/bjma/1240321557. https://projecteuclid.org/euclid.bjma/1240321557

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