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Related papers: Operator log-convex functions and operator means

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We identity the optimal non-infinitesimal direction of descent for a convex function. An algorithm is developed that can theoretically minimize a subset of (non-convex) functions.

Optimization and Control · Mathematics 2025-09-19 Andrew J. Young

We first show that a continuous function f is nonnegative on a closed set $K\subseteq R^n$ if and only if (countably many) moment matrices of some signed measure $d\nu =fd\mu$ with support equal to K, are all positive semidefinite (if $K$…

Optimization and Control · Mathematics 2011-05-13 Jean B. Lasserre

In this paper, we present some operator and eigenvalue inequalities involving operator monotone, doubly concave and doubly convex functions. These inequalities provide some variants of operator Acz\'{e}l inequality and its reverse via…

Functional Analysis · Mathematics 2020-01-16 Shigeru Furuichi , Mohammad Reza Jabbarzadeh , Venus Kaleibary

We show that positively $1$--homogeneous rank one convex functions are convex at $0$ and at matrices of rank one. The result is a special case of an abstract convexity result that we establish for positively $1$--homogeneous directionally…

Analysis of PDEs · Mathematics 2016-03-23 Bernd Kirchheim , Jan Kristensen

In this paper, we introduce the concept of operator arithmetic-geometrically convex functions for positive linear operators and prove some Hermite-Hadamard type inequalities for these functions. As applications, we obtain trace inequalities…

Functional Analysis · Mathematics 2016-03-16 Ali Taghavi , Vahid Darvish , Haji Mohammad Nazari

We prove conditions for the existence of a continuous linear right inverse for a surjective convolution operator in spaces of germs of analytic functions on convex subsets of the complex plane. Considered convex sets have a countable…

Functional Analysis · Mathematics 2018-10-22 S. N. Melikhov , L. V. Khanina

In this paper we investigate continuity properties of functions $f:\mathbb{R}_+\to\mathbb{R}_+$ that satisfy the $(p,q)$-Jensen convexity inequality $$ f\big(H_p(x,y)\big)\leq H_q(f(x),f(y)) \qquad(x,y>0), $$ where $H_p$ stands for the…

Classical Analysis and ODEs · Mathematics 2015-12-24 Gyula Maksa , Zsolt Páles

We introduce and study a new class of nonlinear monotone operators acting in normal cones of real Banach spaces and possessing the property of strong concavity. We establish new constructive principles for the existence of nonzero fixed…

Functional Analysis · Mathematics 2026-04-27 Khachatur A. Khachatryan

Recently, the authors studied the connection between each maximal monotone operator T and a family H(T) of convex functions. Each member of this family characterizes the operator and satisfies two particular inequalities. The aim of this…

Functional Analysis · Mathematics 2008-02-13 Regina Sandra Burachik , B. F. Svaiter

We provide a concise analysis about what is known regarding when the closure of the domain of a maximally monotone operator on an arbitrary real Banach space is convex. In doing so, we also provide an affirmative answer to a problem posed…

Functional Analysis · Mathematics 2012-05-22 Jonathan M. Borwein , Liangjin Yao

This paper is about the technique of {\em shadow variables} that was used in the theory of monotone operators. In this paper, we use it to show that certain results that were originally proved for lower semicontinuous convex functions are…

Functional Analysis · Mathematics 2015-12-14 Stephen Simons

A fundamental open question asking whether all real-valued strongly quasiconvex functions defined on $\mathbb R^n$ are necessarily continuous, akin to their convex counterparts, is answered in detail in this paper. Among other things, we…

Optimization and Control · Mathematics 2025-12-04 Nguyen Thi Van Hang , Felipe Lara , Nguyen Dong Yen

The aim of this paper is to study a wide class of non-convex sweeping processes with moving constraint whose translation and deformation are represented by regulated functions, i.e., functions of not necessarily bounded variation admitting…

Dynamical Systems · Mathematics 2021-01-08 Pavel Krejci , Giselle Antunes Monteiro , Vincenzo Recupero

We give a sufficient and necessary condition for a probability measure $\mu$ on the real line to satisfy the logarithmic Sobolev inequality for convex functions. The condition is expressed in terms of the unique left-continuous and…

Probability · Mathematics 2019-06-18 Yan Shu , Michał Strzelecki

The notion of B-convexity for operator spaces, which a priori depends on a set of parameters indexed by $\Sigma$, is defined. Some of the classical characterizations of this geometric notion for Banach spaces are studied in this new…

Operator Algebras · Mathematics 2007-05-23 Javier Parcet

In this paper we first introduce the Heron and Heinz means of two convex functionals. Afterwards, some inequalities involving these functional means are investigated. The operator versions of our theoretical functional results are…

Functional Analysis · Mathematics 2018-12-20 Mustapha Raïssouli , Shigeru Furuichi

Eigenvalues inequalities involving (log) convex/concav functions and Hermitian matrices, positive unital maps are considered. Simple proofs of Bhatia-Kittaneh inequality and Naimark dilation theorem are given.

Operator Algebras · Mathematics 2007-05-23 Jaspal Singh Aujla Jean-Christophe Bourin

In this article, we first study, in the framework of operator theory, Pusz and Woronowicz's functional calculus for pairs of bounded positive operators on Hilbert spaces associated with a homogeneous two-variable function on $[0,\infty)^2$.…

Functional Analysis · Mathematics 2021-05-21 Fumio Hiai , Yoshimichi Ueda , Shuhei Wada

Discrete convex functions are used in many areas, including operations research, discrete-event systems, game theory, and economics. The objective of this paper is to offer a survey on fundamental operations for various kinds of discrete…

Combinatorics · Mathematics 2019-10-04 Kazuo Murota

In the present work we show that the local generalized monotonicity of a lower semicontinuous set-valued operator on some certain type of dense sets ensures the global generalized monotonicity of that operator. We achieve this goal…

Functional Analysis · Mathematics 2013-10-17 Szilárd László , Adrian Viorel