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Related papers: Jensen's Operator Inequality

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Given a function $f$ defined on a nonempty and convex subset of the $d$-dimensional Euclidean space, we prove that if $f$ is bounded from below and it satisfies a convexity-type functional inequality with infinite convex combinations, then…

Classical Analysis and ODEs · Mathematics 2025-09-16 Matyas Barczy , Zsolt Páles

This short but self-contained survey presents a number of elegant matrix/operator inequalities for general convex or concave functions, obtained with a unitary orbit technique. Jensen, sub or super-additivity type inequalities are…

Functional Analysis · Mathematics 2014-02-26 Jean-Christophe Bourin , Eun-Young Lee

In this paper we obtain some operator versions of Levin-Steckin integral inequality.

Functional Analysis · Mathematics 2020-05-12 Silvestru Sever Dragomir

In this paper we consider the order-like relation for self-adjoint operators on some Hilbert space. This relation is defined by using Jensen inequality. We will show that under some assumptions this relation is antisymmetric.

Functional Analysis · Mathematics 2009-04-17 Tomohiro Hayashi

We study the convergence of a family of numerical integration methods where the numerical integral is formulated as a finite matrix approximation to a multiplication operator. For bounded functions, the convergence has already been…

Numerical Analysis · Mathematics 2023-03-28 Juha Sarmavuori , Simo Särkkä

In this paper, some Jensen's type inequalities between quaternionic bounded selfadjoint operators on quaternionic Hilbert spaces are proved, using a log-convex function. Also, by applying a specific log-convex function, some particular…

Functional Analysis · Mathematics 2025-04-17 Massoumeh Fashandi

In this paper we introduce a new technique for proving norm inequalities in operator ideals with an unitarily invariant norm. Among the well known inequalities which can be proved with this technique are the L\"owner-Heinz inequality,…

Operator Algebras · Mathematics 2008-08-19 Gabriel Larotonda

We develop a new framework for the Jensen-type inequalities that allows us to deal with functions not necessarily convex and Borel measures not necessarily positive.

Classical Analysis and ODEs · Mathematics 2012-07-31 Constantin P. Niculescu , Cătălin Irinel Spiridon

We provide a direct, intersection theoretic, argument that the Jordan models of an operator of class C_{0}, of its restriction to an invariant subspace, and of its compression to the orthogonal complement, satisfy a multiplicative form of…

Functional Analysis · Mathematics 2015-05-27 Hari Bercovici , Wing Suet Li

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

Some sharp inequalities of Gruss type for sequences of vectors in real or complex inner product spaces are obtained. Applications for Jensen's inequality for convex functions defined on such spaces are also provided.

Classical Analysis and ODEs · Mathematics 2025-10-20 Sever Silvestru Dragomir

We study conditional expectations generated by an abelian $ C^* $-subalgebra in the centralizer of a positive functional. We formulate and prove Jensen's inequality for functions of several variables with respect to this type of conditional…

Operator Algebras · Mathematics 2007-05-23 Frank Hansen

In this paper we develop a general method for improving Jensen-type inequalities for convex and, even more generally, for piecewise convex functions. Our main result relies on the linear interpolation of a convex function. As a consequence,…

Classical Analysis and ODEs · Mathematics 2016-10-06 Daeshik Choi , Mario Krnić , Josip Pecarić

We establish that trace inequalities $$\|D^{k-1}u\|_{L^{\frac{n-s}{n-1}}(\mathbb{R}^{n},d\mu)} \leq c \|\mu\|_{L^{1,n-s}(\mathbb{R}^{n})}^{\frac{n-1}{n-s}}\|\mathbb{A}[D]u\|_{L^{1}(\mathbb{R}^{n},d\mathscr{L}^{n})}$$ hold for vector fields…

Analysis of PDEs · Mathematics 2021-12-01 Franz Gmeineder , Bogdan Raita , Jean Van Schaftingen

We study the Mercer inequality and its operator extension for superquadratic functions. In particular, we give a more general form of the Mercer inequality by replacing some constants by positive operators. As some consequences, our results…

Functional Analysis · Mathematics 2024-03-27 Mohsen Kian , Zainab Peymani Mazraj

Let $p$ be a positive number and $h$ a function on $\mathbb{R}^+$ satisfying $h(xy) \ge h(x) h(y)$ for any $x, y \in \mathbb{R}^+$. A non-negative continuous function $f$ on $K (\subset \mathbb{R}^+)$ is said to be {\it operator…

Functional Analysis · Mathematics 2017-12-22 Trung Hoa Dinh , Khue TB Vo

In this paper we study a class of Jacobi operators, such that each operator is generated by the unit Borel measure with a support consisting of a finite number of intervals on the real line R and a finite number of points in C, located…

Complex Variables · Mathematics 2013-10-17 Sergey Suetin

Convex analysis is fundamental to proving inequalities that have a wide variety of applications in economics and mathematics. In this paper we provide Jensen-type inequalities for functions that are, intuitively, "very" convex. These…

Optimization and Control · Mathematics 2021-08-10 Bar Light

We establish in this paper some inequalities for analytic and convex functions on an open interval and positive normalized functionals defined on a Hermitian unital Banach *-algebra. Reverses and refinements of Jensen's and Slater's type…

Functional Analysis · Mathematics 2016-12-20 Silvestru Sever Dragomir

In this paper, we investigate the relative operator entropies in the more general settings of C*-algebras, real C*-algebras and JC-algebras. We show that all the operator inequalities on relative operator entropies still hold in these…

Operator Algebras · Mathematics 2020-12-24 Shuzhou Wang , Zhenhua Wang