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Related papers: Generalizations of Reid Inequality

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Let $A=A^*$ be a linear operator in a Hilbert space $H$. Assume that equation $Au=f \quad (1)$ is solvable, not necessarily uniquely, and $y$ is its minimal-norm solution. Assume that problem (1) is ill-posed. Let $f_\d$, $||f-f_d||\leq…

Numerical Analysis · Mathematics 2007-05-23 A. G. Ramm

In this paper, we derive a generalized multiplicative Hardy-Littlewood-Polya type inequality, as well as several related additive inequalities, for functions of operators in Hilbert spaces. In addition, we find the modulus of continuity of…

Functional Analysis · Mathematics 2015-10-06 Vladyslav Babenko , Yuliya Babenko , Nadiia Kriachko

In this paper, we show refined Young inequalities for two positive operators. Our results refine the ordering relations among the arithmetic mean, the geometric mean and the harmonic mean for two positive operators. In addition, we give two…

Functional Analysis · Mathematics 2011-04-26 Shigeru Furuichi

The purpose of this paper is to generalize a very famous result on products of normal operators, due to I. Kaplansky. The context of generalization is that of bounded hyponormal and unbounded normal operators on complex separable Hilbert…

Functional Analysis · Mathematics 2014-03-04 Abdelkader Benali , Mohammed Hichem Mortad

In this paper a reduction and equivalence theorems for the boundedness of the composition of a quasilinear operator $T$ with the Hardy and Copson operators in weighted Lebesgue spaces are proved. New equivalence theorems are obtained for…

Classical Analysis and ODEs · Mathematics 2015-03-16 Amiran Gogatishvili , Rza Mustafayev

New inequalities for the numerical radius of bounded linear operators defined on a complex Hilbert space $\mathcal{H}$ are given. In particular, it is established that if $T$ is a bounded linear operator on a Hilbert space $\mathcal{H}$…

Functional Analysis · Mathematics 2024-08-14 Pintu Bhunia , Kallol Paul

This paper establishes several new inequalities for the $A$-norm and $A$-numerical radius of operator sums in semi-Hilbertian spaces, significantly advancing the existing theory. We present two fundamental refinements of the generalized…

Functional Analysis · Mathematics 2025-07-09 M. H. M. Rashid

In this work, some generalizations and refinements inequalities for numerical radius of the product of Hilbert space operators are proved. New inequalities for numerical radius of block matrices of Hilbert space operators are also…

Functional Analysis · Mathematics 2019-03-18 Mohammad W. Alomari

This paper aims to characterize the function appearing in the weighted Hermite-Hadamard inequality. We provide improved inequalities for the weighted means as applications of the obtained results. Modifications of the weighted…

General Mathematics · Mathematics 2023-01-02 Shigeru Furuichi , Nicuşor Minculete , Hamid Reza Moradi

In this paper, we obtain a new class of functions, which is developed via the Hermite--Hadamard inequality for convex functions. The well-known one-one correspondence between the class of operator monotone functions and operator connections…

Functional Analysis · Mathematics 2021-07-23 R. Pal , M. Singh , M. S. Moslehian , J. S. Aujla

The Hardy-Rellich inequality given here generalizes a Hardy inequality of Davies (1984), from the case of the Dirichlet Laplacian of a region $\Omega\subseteq\real^N$ to that of the higher order polyharmonic operators with Dirichlet…

Spectral Theory · Mathematics 2007-05-23 Mark P. Owen

In this article, we obtain several new weighted bounds for the numerical radius of a Hilbert space operator. The significance of the obtained results is the way they generalize many existing results in the literature; where certain values…

Functional Analysis · Mathematics 2021-03-09 Shiva Sheybani , Mohammed Sababheh , Hamid Reza Moradi

We give improvements and generalizations of both the classical Hardy inequality and the geometric Hardy inequality based on the divergence theorem. Especially, our improved Hardy type inequality derives both two Hardy type inequalities with…

Analysis of PDEs · Mathematics 2021-04-06 Megumi Sano

We present an inequality for tensor product of positive operators on Hilbert spaces by considering the tensor product of operators as words on certain alphabets (i.e., a set of letters). As applications of the operator inequality and by a…

Functional Analysis · Mathematics 2015-02-23 Xaixia Chang , Vehbi E. Paksoy , Fuzhen Zhang

Some inequalities for positive linear maps on matrix algebras are given, especially asymmetric extensions of Kadison's inequality and several operator versions of Chebyshev's inequality. We also discuss well-known results around the matrix…

Functional Analysis · Mathematics 2010-03-12 Jean-Christophe Bourin , Éric Ricard

We investigate the Hardy and Rellich inequalities for classes of antisymmetric and odd functions and general exponent $p$. The obtained constants are better than the classical ones.

Classical Analysis and ODEs · Mathematics 2024-04-30 Michał Kijaczko

We generalize McDiarmid's inequality for functions with bounded differences on a high probability set, using an extension argument. Those functions concentrate around their conditional expectations. We further extend the results to…

Machine Learning · Computer Science 2024-05-03 Richard Combes

In this article we prove new inequalities for the generalized and the joint spectral radius of bounded sets of positive operators on Banach function and sequence spaces, in particular some inequalities for positive kernel operators that…

Functional Analysis · Mathematics 2023-11-07 Katarina Bogdanović

In this paper, we study refinements of some inequalities related to Young inequality for scalar and for operator. As our main results, we show refined Young inequalities for two positive operators. This results refine the ordering relations…

Functional Analysis · Mathematics 2012-01-27 Shigeru Furuichi , Minghua Lin

An algebraic Riccati equation for linear operators is studied, which arises in systems theory. For the case that all involved operators are unbounded, the existence of infinitely many selfadjoint solutions is shown. To this end, invariant…

Functional Analysis · Mathematics 2013-11-12 Christian Wyss