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Related papers: Operator inequalities related to weak 2-positivity

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We extend Hardy's inequality from sequences of non-negative numbers to sequences of positive semi-definite operators if the parameter p satisfies 1<p<=2, and to operators under a trace for arbitrary p>1. Applications to trace functions are…

Operator Algebras · Mathematics 2010-01-13 Frank Hansen

In this article, we present several inequalities treating operator means and the Cauchy-Schwarz inequality. In particular, we present some new comparisons between operator Heron and Heinz means, several generalizations of the difference…

Functional Analysis · Mathematics 2021-07-23 Y. Kapil , C. Conde , M. S. Moslehian , M. Singh , M. Sababheh

We present a Diaz--Metcalf type operator inequality as a reverse Cauchy-Schwarz inequality and then apply it to get the operator versions of P\'{o}lya-Szeg\"{o}'s, Greub-Rheinboldt's, Kantorovich's, Shisha-Mond's, Schweitzer's, Cassels' and…

Functional Analysis · Mathematics 2012-03-22 M. S. Moslehian , R. Nakamoto , Y. Seo

In this paper, we study operator mean inequalities for the weighted arithmetic, geometric and harmonic means. We give a slight modification of Audenaert's result to show the relation between Kwong functions and operator monotone functions.…

Functional Analysis · Mathematics 2024-05-10 Nahid Gharakhanlu , Mohammad Sal Moslehian , Hamed Najafi

In this paper we present some inequalities involving operator decreasing functions and operator means. These inequalities provide some reverses of operator Acz\'el inequality dealing with the weighted geometric mean.

Functional Analysis · Mathematics 2018-04-17 Venus Kaleibary , Shigeru Furuichi

We prove some refinements of an inequality due to X. Zhan in an arbitrary complex Hilbert space by using some results on the Heinz inequality. We present several related inequalities as well as new variants of the Corach--Porta--Recht…

Functional Analysis · Mathematics 2012-03-21 Cristian Conde , Mohammad Sal Moslehian , Ameur Seddik

We give an extension of Hua's inequality in pre-Hilbert $C^*$-modules without using convexity or the classical Hua's inequality. As a consequence, some known and new generalizations of this inequality are deduced. Providing a Jensen…

Operator Algebras · Mathematics 2010-05-31 Mohammad Sal Moslehian

We give an upper bound for the weighted geometric mean using the weighted arithmetic mean and the weighted harmonic mean. We also give a lower bound for the weighted geometric mean. These inequalities are proven for two invertible positive…

Functional Analysis · Mathematics 2014-10-21 Shigeru Furuichi

We introduce and study a new class of operators that we call disjoint weak Banach-Saks operators. We establish some characterizations of this class of operators by different types of convergence (norm convergence, unbounded order…

Functional Analysis · Mathematics 2021-11-30 Mohamed Berka , Moulay othman Aboutafail , Jawad H'michane

We apply the inequality $\left|\left<x,y\right>\right|\le\|x\|\,\left<y,y\right>^{1/2}$ to give an easy and elementary proof of many operator inequalities for elementary operators and inner type product integral transformers obtained during…

Functional Analysis · Mathematics 2018-01-25 Dragoljub J. Kečkić

We extend an operator P\'{o}lya--Szeg\"{o} type inequality involving the operator geometric mean to any arbitrary operator mean under some mild conditions. Utilizing the Mond--Pe\v{c}ari\'c method, we present some other related operator…

Functional Analysis · Mathematics 2017-09-26 D. T. Hoa , M. S. Moslehian , C. Conde , P. Zhang

We give a Jensen operator inequality for strongly convex functions. As a corollary, we improve operator Holder-McCarthy inequality under suitable conditions.

Functional Analysis · Mathematics 2017-02-07 H. R. Moradi , R. Naseri

Let $L$ be a linear operator in $L^2(\mathbb{R}^n)$ which generates a semigroup $e^{-tL}$ whose kernels $p_t(x,y)$ satisfy the Gaussian upper bound. In this paper, we investigate several kinds of weighted norm inequalities for the conical…

Classical Analysis and ODEs · Mathematics 2020-11-24 Mingming Cao , Zengyan Si , Juan Zhang

A considerable amount of literature in the theory of inequality is devoted to the study of Jensen's and Young's inequality. This article presents a number of new inequalities involving the log-convex functions and the geometrically convex…

Classical Analysis and ODEs · Mathematics 2022-02-10 Shigeru Furuichi , Hamid Reza Moradi , Supriyo Dutta

New sharp multiplicative reverses of the operator means inequalities are presented, with a simple discussion of squaring an operator inequality. As a direct consequence, we extend the operator P\'olya-Szeg\"o inequality to arbitrary…

Functional Analysis · Mathematics 2018-04-06 Shigeru Furuichi , Hamid Reza Moradi , Mohammad Sababheh

We establish some weighted $L^2$ inequalities for Fourier extension operators in the setting of orthonormal systems. In the process we develop a direct approach to such inequalities based on generalised Wigner distributions, complementing…

Classical Analysis and ODEs · Mathematics 2025-06-12 Jonathan Bennett , Neal Bez , Susana Gutierrez , Shohei Nakamura , Itamar Oliveira

This article improves the triangle inequality for complex numbers, using the Hermite-Hadamard inequality for convex functions. Then, applications of the obtained refinement are presented to include some operator inequalities. The operator…

Functional Analysis · Mathematics 2022-04-19 Shigeru Furuichi , Mohammad Sababheh , Hamid Reza Moradi

In this paper, we obtain the subadditivity inequality of strongly operator convex functions on $(0, \infty)$ and $(-\infty,0)$. Applying the properties of operator convex functions, we deduce the subadditivity property of operator monotone…

Functional Analysis · Mathematics 2024-05-10 Nahid Gharakhanlu , Mohammad Sal Moslehian

We establish several operator versions of the classical Aczel inequality. One of operator versions deals with the weighted operator geometric mean and another is related to the positive sesquilinear forms. Some applications including the…

Functional Analysis · Mathematics 2012-03-22 Mohammad Sal Moslehian

In this paper we use basic properties of strongly convex functions to obtain new inequalities including Jensen's type and Jensen-Mercer type inequalities. Applications for special means are pointed out as well. We also give a Jensen's…

Functional Analysis · Mathematics 2017-07-06 H. R. Moradi , M. E. Omidvar , M. Adil Khan , K. Nikodem
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