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Related papers: Convexity of a certain operator trace functional

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In this paper, the connection between the functional inequalities $$ f\Big(\frac{x+y}{2}\Big)\leq\frac{f(x)+f(y)}{2}+\alpha_J(x-y) \qquad (x,y\in D)$$ and $$ \int_0^1f\big(tx+(1-t)y\big)\rho(t)dt \leq\lambda f(x)+(1-\lambda)f(y)…

Classical Analysis and ODEs · Mathematics 2012-12-06 Judit Makó , Zsolt Páles

Operator scrambling is a crucial ingredient of quantum chaos. Specifically, in the quantum chaotic system, a simple operator can become increasingly complicated under unitary time evolution. This can be diagnosed by various measures such as…

Strongly Correlated Electrons · Physics 2018-04-25 Xiao Chen , Tianci Zhou

We study here the elementary properties of the relative entropy $\cH(A,B)=\tr[\phi(A)-\phi(B)-\phi'(B)(A-B)]$ for $\phi$ a convex function and $A,B$ bounded self-adjoint operators. In particular, we prove that this relative entropy is…

Mathematical Physics · Physics 2015-06-17 Mathieu Lewin , Julien Sabin

The main target of this paper is to discuss operator Hermite--Hadamard inequality for convex functions, without appealing to operator convexity. Several forms of this inequality will be presented and some applications including norm and…

Functional Analysis · Mathematics 2019-08-07 Hamid Reza Moradi , Mohammad Sababheh , Shigeru Furuichi

For finite-dimensional operator systems $\mathcal{S}_{\mathsf T}$, ${\mathsf T} \in B({\mathcal H})^d$, we show that the local lifting property and $1$-exactness of $\mathcal{S}_{\mathsf T}$ may be characterized by measurements of the…

Functional Analysis · Mathematics 2021-06-09 Benjamin Passer , Vern I. Paulsen

Four possible definitions of the commutation relation $[S,T]=\Id$ of two closable unbounded operators $S,T$ are compared. The {\em weak} sense of this commutator is given in terms of the inner product of the Hilbert space $\H$ where the…

Mathematical Physics · Physics 2015-06-03 Fabio Bagarello , Atsushi Inoue , Camillo Trapani

Trace formulas appear in many forms in noncommutative geometry (NCG). In the first part of this thesis, we obtain results for asymptotic expansions of trace formulas like heat trace expansions by adapting the theory of Multiple Operator…

Operator Algebras · Mathematics 2025-06-30 Eva-Maria Hekkelman

In this paper we develop a general theoretical tool for the establishment of the boundedness of notoriously difficult operators (such as potentials) on certain specific types of rearrangement-invariant function spaces from analogous…

Functional Analysis · Mathematics 2026-02-16 Zdeněk Mihula , Luboš Pick , Daniel Spector

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

The main object considered in this paper is the trace function, defined as a suitably normalized trace of a product of intertwining operators for the Drinfeld-Jimbo quantum group, multiplied by the exponential of an element of the Cartan…

Quantum Algebra · Mathematics 2007-05-23 Pavel Etingof , Alexander Varchenko

We study the convexity properties of the generalized trigonometric functions considered as functions of parameter. We show that $p\to\sin_p(y)$ and $p\to\cos_p(y)$ are log-concave on the appropriate intervals while $p\to\tan_p(y)$ is…

Classical Analysis and ODEs · Mathematics 2014-02-17 D. B. Karp , E. G. Prilepkina

A general method for proving continuity of the von Neumann entropy on subsets of positive trace-class operators is considered. This makes it possible to re-derive the known conditions for continuity of the entropy in more general forms and…

Mathematical Physics · Physics 2015-05-13 M. E. Shirokov

Frame theory is recently an active research area in mathematics, computer science, and engineering with many exciting applications in a variety of different fields. In this paper, we firstly give a characterization of operator frame for…

Functional Analysis · Mathematics 2019-05-06 Mohamed Rossafi , Abdellatif Akhlidj

The main result (roughly) is that if (H_i) converges weakly to H and if also f(H_i) converges weakly to f(H), for a single strictly convex continuous function f, then (H_i) must converge strongly to H. One application is that if f(pr(H)) =…

Functional Analysis · Mathematics 2017-06-09 Lawrence G. Brown

We prove a logarithmic Sobolev trace inequality in a gaussian space and we study the trace operator in the weighted Sobolev space W^{1,p}(\Omega,\gamma) for sufficiently regular domain. We exhibit examples to show the sharpness of the…

Functional Analysis · Mathematics 2011-01-20 F. Feo , M. R. Posteraro

To study operator algebras with symmetries in a wide sense we introduce a notion of {\em relative convolution operators} induced by a Lie algebra. Relative convolutions recover many important classes of operators, which have been already…

funct-an · Mathematics 2008-02-03 Vladimir V. Kisil

We give a necessary and sufficient condition for strict convexity of the rate function of a random vector in $R^d$. This condition is always satisfied when the random vector has finite Laplace transform. We also completely describe the…

Probability · Mathematics 2021-06-17 Vladislav Vysotsky

We define in the space of n by m matrices of rank n, n less or equal than m, the condition Riemannian structure as follows: For a given matrix A the tangent space of A is equipped with the Hermitian inner product obtained by multiplying the…

Numerical Analysis · Mathematics 2010-07-12 Carlos Beltrán , Jean-Pierre Dedieu , Gregorio Malajovich , Mike Shub

In the present paper, we consider a convex combination of non-Volterra quadratic stochastic operators defined on a finite-dimensional simplex depending on a parameter $\alpha$ and study their trajectory behaviors. We showed that for any…

Dynamical Systems · Mathematics 2026-01-27 Uygun Jamilov , Manuel Ladra

Convex functions have played a major role in the field of Mathematical inequalities. In this paper, we introduce a new concept related to convexity, which proves better estimates when the function is somehow more convex than another. In…

Functional Analysis · Mathematics 2020-03-25 M. Sababheh , S. Furuichi , H. R. Moradi