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Related papers: Convex inequalities in Hilbert $C^*$-modules

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Some new Hermite-Hadamard's inequalities for h-convex functions are proved, generalizing and unifying a number of known results. Some new applications for special Means of real numbers are also derived.

Classical Analysis and ODEs · Mathematics 2015-11-18 Muhammad Iqbal , Muhammad Muddassar , Muhammad Iqbal Bhatti

In this paper, we introduce the notion of invariant submodule in the theory of Hilbert C*-modules and study some basic properties of bounded adjointable operators and their generalized inverses which have nontrivial invariant submodules. We…

Operator Algebras · Mathematics 2025-06-03 Kamran Sharifi

We continue our study of the general theory of possibly nonselfadjoint algebras of operators on a Hilbert space, and modules over such algebras, developing a little more technology to connect `nonselfadjoint operator algebra' with the…

Operator Algebras · Mathematics 2007-05-23 David P. Blecher

We survey several significant results on the Bohr inequality and presented its generalizations in some new approaches. These are some Bohr type inequalities of Hilbert space operators related to the matrix order and the Jensen inequality.…

Functional Analysis · Mathematics 2011-07-08 Masatoshi Fujii , Mohammad Sal Moslehian , Jadranka Micic

A Hilbert $C^*$-quad module of finite type has a multi structure of Hilbert $C^*$-bimodules with two finite bases. We will construct a $C^*$-algebra from a Hilbert $C^*$-quad module of finite type and prove its universality subject to…

Operator Algebras · Mathematics 2013-10-01 Kengo Matsumoto

Utilizing the Birkhoff--James orthogonality, we present some characterizations of the norm-parallelism for elements of $\mathbb{B}(\mathscr{H})$ defined on a finite dimensional Hilbert space, elements of a Hilbert $C^*$-module over the…

Operator Algebras · Mathematics 2021-07-23 Ali Zamani , Mohammad Sal Moslehian

Considering some parameters and by means of an inequality of Hadamard, we derive general half-discrete Hilbert-type inequalities. Then we highlight some special cases.

Functional Analysis · Mathematics 2016-01-06 Waleed Abuelela

The aim of this paper is to generalize the Hermite--Hadamard inequality for functions convex on the coordinates. Our composite result generalizes the result of Dragomir in \cite{Drag}. Many other interesting inequalities can be derived from…

Classical Analysis and ODEs · Mathematics 2018-01-01 Eze R. Nwaeze

Hilbert C*-modules are the analogues of Hilbert spaces where a C*-algebra plays the role of the scalar field. With the advent of Kasparov's celebrated KK-theory they became a standard tool in the theory of operator algebras. While the…

Operator Algebras · Mathematics 2016-12-23 Jens Kaad , Matthias Lesch

New proofs of the classical Hermite-Hadamard inequality are presented and several applications are given, including Hadamard-type inequalities for the functions, whose derivatives have inflection points or whose derivatives are convex.…

General Mathematics · Mathematics 2020-10-14 Ilham A. Aliev , Mehmet E. Tamar , Cagla Sekin

In this paper, we study three types of Birkhoff-James orthogonality in Hilbert $C^*$-modules, that is, the strong, quasi-strong, and original Birkhoff-James orthogonality. In general, the strong Birkhoff-James orthogonality is stronger than…

Functional Analysis · Mathematics 2025-11-20 Soumitra Daptari , Koki Igarashi , Jumpei Nakamura , Ryotaro Tanaka

In this paper, we state some characterizations of $h$-convex function is defined on a convex set in a linear space. By doing so, we extend the Jensen-Mercer inequality for $h$-convex function. We will also define $h$-convex function for…

Functional Analysis · Mathematics 2020-03-31 M. Abbasi , A. Morassaei , F. Mirzapour

In the present paper we establish some new integral inequalities analogous to the well known Hadamard inequality by using a fairly elementary analysis.

Classical Analysis and ODEs · Mathematics 2012-01-16 Mevlut Tunc , S. Ugur Kirmaci

In this paper, a general form of integral inequalities of Hermite-Hadamard's type through differentiability for s-Convex function in second sense and whose all derivatives are absolutely continuous are established. The generalized integral…

Functional Analysis · Mathematics 2013-06-25 Muhammad Muddassar , Muhammad Iqbal Bhatti

This paper deals mainly with some aspects of the adjointable operators on Hilbert $C^*$-modules. A new tool called the generalized polar decomposition for each adjointable operator is introduced and clarified. As an application, the general…

Functional Analysis · Mathematics 2024-04-25 Xiaofeng Zhang , Xiaoyi Tian , Qingxiang Xu

The goal of the present paper is to extend the theory of frames for countably generated Hilbert $C^*$-modules over arbitrary $C^*$-algebras. In investigating the non-unital case we introduce the concept of outer frame as a sequence in the…

Operator Algebras · Mathematics 2015-07-16 Ljiljana Arambašić , Damir Bakić

H\"{o}lder's inequality, since its appearance in 1888, has played a fundamental role in Mathematical Analysis and it is, without any doubt, one of the milestones in Mathematics. It may seem strange that, nowadays, it keeps resurfacing and…

Functional Analysis · Mathematics 2015-03-31 N. Albuquerque , G. Araujo , D. Pellegrino , J. Seoane-Sepulveda

We present three versions of the Lax-Milgram theorem in the framework of Hilbert C*-modules, two for those over W*-algebras and one for those over C*-algebras of compact operators. It is remarkable that while the Riesz theorem is not valid…

Operator Algebras · Mathematics 2025-04-29 R. Eskandari , M. Frank , V. M. Manuilov , M. S. Moslehian

In the present paper the notion of continuous frames is introduced and some results of these frames are proved. Next, we give the concept of duals of continuous frames in Hilbert C*-modules and investigate some properties of them.

Functional Analysis · Mathematics 2023-01-24 Hadi Ghasemi , Tayebe Lal Shateri

Theory of extensions of Hilbert C*-modules was developed by D. Bakic and B. Guljas. An easy observation shows that in the case, when the underlying C*-algebra extension is commutative and the Hilbert C*-modules are projective of finite…

Operator Algebras · Mathematics 2012-03-20 Vladimir Manuilov , Jingming Zhu