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Related papers: Strongly subadditive functions

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Let $F$ be a field and a finite $A\subset F$ be sufficiently small in terms of the characteristic $p$ of $F$ if $p>0$. We strengthen the "threshold" sum-product inequality $$|AA|^3 |A\pm A|^2 \gg |A|^6\,,\;\;\;\;\mbox{hence} \;\;…

Combinatorics · Mathematics 2018-09-27 Misha Rudnev , George Shakan , Ilya Shkredov

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

The Additive Transform of an arithmetic function represents a novel approach to examining the interplay between multiplicative arithmetic function and additive functions. This transform concept introduces a method to systematically generate…

General Mathematics · Mathematics 2023-12-15 E. En-naoui

We expand the theoretical background of the recently introduced superadditive and subadditive transformations of aggregation functions $A$. Necessary and sufficient conditions ensuring that a transformation of a proper aggregation function…

Functional Analysis · Mathematics 2016-01-05 Alexandra Šipošová

It is known that the function $f(e^x)/g(e^x)$ is positive definite for some functions $f,g$ implies the operator norm inequality related to $f,g$. We treat functions which have the following form: $f(t) = t^{(1-\sum_{i=1}^n…

Functional Analysis · Mathematics 2016-10-25 Imam Nugraha Albania , Masaru Nagisa

We show that the symmetrized product $AB+BA$ of two positive operators $A$ and $B$ is positive if and only if $f(A+B)\leq f(A)+f(B)$ for all non-negative operator monotone functions $f$ on $[0,\infty)$ and deduce an operator inequality. We…

Functional Analysis · Mathematics 2012-03-21 M. S. Moslehian , H. Najafi

The aim of this article is twofold: give a short proof of the existence of real spectral shift function and the associated trace formula for a pair of contractions, the difference of which is trace-class and one of the two a strict…

Functional Analysis · Mathematics 2021-02-15 Arup Chattopadhyay , Kalyan B. Sinha

Trace classes of Sobolev-type functions in metric spaces are subject of this paper. In particular, functions on domains whose boundary has an upper codimension-$\theta$ bound are considered. Based on a Poincar\'e inequality, existence of a…

Metric Geometry · Mathematics 2017-04-24 Lukáš Malý

We study functional inequality of the form $$|T(f,h)-T(f,g)T(g,h)| \leq F(f,g)F(g,h) -F(f,h)$$ where $T$ is a complex-valued functional and $F$ is a real-valued map. Motivation for our studies comes from some generalizations of Gr\"uss…

Classical Analysis and ODEs · Mathematics 2019-06-06 Włodzimierz Fechner

Given an integer $a\ge 1$, a function $f: \mathbb{R}\to \mathbb{R}$ is said to be $a$-subadditive if $$ f(ax+y) \le af(x)+f(y) \,\,\,\text{ for all }x,y \in \mathbb{R}. $$ Of course, $1$-subadditive functions (which correspond to ordinary…

Classical Analysis and ODEs · Mathematics 2025-09-16 Paolo Leonetti

In this note we study restrictions on the recently introduced super-additive and sub-additive transformations, $A\mapsto A^*$ and $A\mapsto A_*$, of an aggregation function $A$. We prove that if $A^*$ has a slightly stronger property of…

Functional Analysis · Mathematics 2016-07-14 Alexandra Šipošová , Ladislav Šipeky , Jozef Širáň

Simple inequalities for some integrals involving the modified Struve function of the first kind $\mathbf{L}_{\nu}(x)$ are established. In most cases, these inequalities have best possible constant. We also deduce a tight double inequality,…

Classical Analysis and ODEs · Mathematics 2018-07-13 Robert E. Gaunt

In this short paper, we give a complete and affirmative answer to a conjecture on matrix trace inequalities for the sum of positive semidefinite matrices. We also apply the obtained inequality to derive a kind of generalized Golden-Thompson…

Functional Analysis · Mathematics 2010-08-23 Shigeru Furuichi , Minghua Lin

Let $A$ and $B$ be compact operators over a topological space $X$ and suppose that these operators are normal and have same distinct eigenvalues at each point. By obstruction theory, we establish a necessary and sufficient condition for $A$…

Functional Analysis · Mathematics 2017-09-04 Jingming Zhu

We present some reverse Young-type inequalities for the Hilbert-Schmidt norm as well as any unitarily invariant norm. Furthermore, we give some inequalities dealing with operator means. More precisely, we show that if $A, B\in {\mathfrak…

Functional Analysis · Mathematics 2021-07-23 Mojtaba Bakherad , Mario Krnic , Mohammad Sal Moslehian

We establishe an affine Hardy-Littlewood-Sobolev inequality concerning two different functions which is stronger than the classical Hardy-Littlewood-Sobolev inequality. Furthermore, we also prove reverse inequalities for the new…

Functional Analysis · Mathematics 2025-08-05 Youjiang Lin , Jinghong Zhou , Jiaming Lan

By the help of power series f we can naturally construct another power series that has as coefficients the absolute values of the coefficients of f. Utilising these functions we prove some inequalities for the spectral radius of the bounded…

Functional Analysis · Mathematics 2013-02-13 S. S. Dragomir

The existence of extremal functions for the Sobolev trace inequalities is studied using the concentration compactness theorem. The conjectured extremal, the function of conformal factor, is considered and is proved to be an actual extremal…

Classical Analysis and ODEs · Mathematics 2007-05-23 Young Ja Park

For any densely defined, lower semi-continuous trace \tau on a C*-algebra A with mutually commuting C*-subalgebras A_1, A_2, ... A_n, and a convex function f of n variables, we give a short proof of the fact that the function (x_1, x_2,…

Operator Algebras · Mathematics 2015-06-26 Elliott H. Lieb , Gert K. Pedersen

We introduce a notion of positive definiteness for functions $f\!:P\to\mathbb{R}$ defined on meet semilattices $(P,\preceq,\wedge)$ and prove several properties for these functions. In addition, we utilize the $LDL^{\rm T}$ decomposition of…

Number Theory · Mathematics 2020-04-29 Vesa Kaarnioja , Pentti Haukkanen , Pauliina Ilmonen , Mika Mattila