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Related papers: Operator monotone functions of several variables

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We investigate operator-valued monotone independence, a noncommutative version of independence for conditional expectation. First we introduce operator-valued monotone cumulants to clarify the whole theory and show the moment-cumulant…

Operator Algebras · Mathematics 2014-09-09 Takahiro Hasebe , Hayato Saigo

Approximations of functions with finite data often do not respect certain "structural" properties of the functions. For example, if a given function is non-negative, a polynomial approximation of the function is not necessarily also…

Numerical Analysis · Mathematics 2020-08-20 Vidhi Zala , Robert M. Kirby , Akil Narayan

The connection between monotonicity formulas and the (S$_+$)-property is that, for some popular differential operators, the former is used to prove the latter. The purpose of this paper is to explore this connection, remark how in the past…

Analysis of PDEs · Mathematics 2024-08-28 Ángel Crespo-Blanco

The concept of sequential choice functions is introduced and studied. This concept applies to the reduction of the problem of stable matchings with sequential workers to a situation where the workers are linear.

Combinatorics · Mathematics 2024-03-26 Vladimir I. Danilov

The notion of monogenic (or regular) functions, which is a correspondence of holomorphic functions, has been studied extensively in hypercomplex analysis, including quaternionic, octonionic, and Clifford analysis. Recently, the concept of…

Complex Variables · Mathematics 2026-05-19 Zhenghua Xu , Chao Ding , Haiyan Wang

Given a function $f: (a,b) \rightarrow \mathbb{R},$ L\"owner's theorem states $f$ is monotone when extended to self-adjoint matrices via the functional calculus, if and only if $f$ extends to a self-map of the complex upper half plane. In…

Operator Algebras · Mathematics 2017-06-27 J. E. Pascoe

We introduce and study logic programs whose clauses are built out of monotone constraint atoms. We show that the operational concept of the one-step provability operator generalizes to programs with monotone constraint atoms, but the…

Artificial Intelligence · Computer Science 2007-05-23 V. W. Marek , I. Niemela , M. Truszczynski]

It is known that for convex sets, the KKM condition is equivalent to the finite intersection property. We use this equivalence to obtain a characterisation of monotone operators in terms of convex KKM maps and in terms of the existence of…

Optimization and Control · Mathematics 2015-03-24 Marc Lassonde

In the paper, necessary and sufficient conditions are presented for a function involving a ratio of gamma functions to be logarithmically completely monotonic. This extends and generalizes the main result in [\emph{Inequalities and…

Classical Analysis and ODEs · Mathematics 2012-08-21 Feng Qi , Bai-Ni Guo

In this paper our aim is to prove some monotonicity and convexity results for the modified Struve function of the second kind by using its integral representation. Moreover, as consequences of these results, we present some functional…

Classical Analysis and ODEs · Mathematics 2015-01-28 Árpád Baricz , Tibor K. Pogány

A new stochastic primal--dual algorithm for solving a composite optimization problem is proposed. It is assumed that all the functions/operators that enter the optimization problem are given as statistical expectations. These expectations…

Optimization and Control · Mathematics 2020-06-23 Pascal Bianchi , Walid Hachem , Adil Salim

We introduce and investigate a new generalized convexity notion for functions called prox-convexity. The proximity operator of such a function is single-valued and firmly nonexpansive. We provide examples of (strongly) quasiconvex, weakly…

Optimization and Control · Mathematics 2021-11-30 Sorin-Mihai Grad , Felipe Lara

There are given conditions for represention of a function of many arguments as the difference of convex functions.

Optimization and Control · Mathematics 2025-09-08 Igor Proudnikov

In this paper, the notion of simultaneous universality is introduced, concerning operators having orbits that simultaneously approximate any given vector. This notion is related to the well known concepts of universality and disjoint…

Functional Analysis · Mathematics 2017-01-26 Luis Bernal-González , Andreas Jung

We introduce the notion of regular operator mappings of several variables generalising the notion of spectral function. This setting is convenient for studying maps more general than what can be obtained from the functional calculus, and it…

Functional Analysis · Mathematics 2014-07-23 Frank Hansen

Many contemporary applications in signal processing and machine learning give rise to structured non-convex non-smooth optimization problems that can often be tackled by simple iterative methods quite effectively. One of the keys to…

Optimization and Control · Mathematics 2020-06-29 Jiajin Li , Anthony Man-Cho So , Wing-Kin Ma

Replacing operators with continuous operator-valued functions, we prove time-dependent versions of well-known results on compressions and diagonals of bounded operators. The setting of smooth functions is also addressed. Our results have no…

Functional Analysis · Mathematics 2025-12-18 Vladimir Müller , Yuri Tomilov

Recently, P\'{a}lfia introduced a generalized Karcher mean as a solution of an operator equation. In this article, we present several relations for this new mean. In particular, we investigate the behavior of this generalized mean when…

Functional Analysis · Mathematics 2019-06-27 Mohammed Sababheh , Hamid Reza Moradi , Zahra Heydarbeygi

This paper is mainly devoted to studying operator Jensen inequality. More precisely, a new generalization of Jensen inequality and its reverse version for convex (not necessary operator convex) functions have been proved. Several special…

Functional Analysis · Mathematics 2019-06-10 M. Shah Hosseini , H. R. Moradi , B. Moosavi

We analyze matrix convex functions of a fixed order defined on a real interval by differential methods as opposed to the characterization in terms of divided differences given by Kraus. We obtain for each order conditions for matrix…

Operator Algebras · Mathematics 2007-05-23 Frank Hansen , Jun Tomiyama