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Related papers: A note on real operator monotone functions

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Some identities for noncommutative perspectives of operator monotone functions in Hilbert spaces aregiven. Applications for weighted operator geometric mean and relative operator entropy are also provided.

Functional Analysis · Mathematics 2020-09-02 Silvestru Sever Dragomir

We study in this paper properties of functions of perturbed normal operators and develop earlier results obtained in \cite{APPS2}. We study operator Lipschitz and commutator Lipschitz functions on closed subsets of the plane. For such…

Functional Analysis · Mathematics 2014-02-26 Aleksei Aleksandrov , Vladimir Peller

We study Toeplitz operators with respect to a commuting $n$-tuple of bounded operators which satisfies some additional conditions coming from complex geometry. Then we consider a particular such tuple on a function space. The algebra of…

Functional Analysis · Mathematics 2022-07-08 Tirthankar Bhattacharyya , B. Krishna Das , Haripada Sau

This paper solves the rational noncommutative analog of Hilbert's 17th problem: if a noncommutative rational function is positive semidefinite on all tuples of hermitian matrices in its domain, then it is a sum of hermitian squares of…

Rings and Algebras · Mathematics 2021-08-23 Jurij Volčič

In this paper, we will show a new characterization of operator monotone functions by a matrix reverse Cauchy inequality.

Functional Analysis · Mathematics 2015-12-14 Dinh Trung Hoa

A real arithmetic function f is multiplicatively monotonous if f (mn) -- f (m) has constant sign for m, n positive integers. Properties and examples of such functions are discussed, with applications to positive hermitian…

Number Theory · Mathematics 2018-09-25 Michel Balazard

We consider a class of monotone operators which are appropriate for symbolic representation and manipulation within a computer algebra system. Various structural properties of the class (e.g., closure under taking inverses, resolvents) are…

Optimization and Control · Mathematics 2018-05-28 Florian Lauster , D. Russell Luke , Matthew K. Tam

For an operator monotone function $f(t)$ on the positive real line, we show the operator monotonicity of the type of the functions $(t-a)(t-b)/(f(t)-f(a))(f^\sharp(t)-f^\sharp(b))$.

Functional Analysis · Mathematics 2012-06-26 Masato Kawasaki , Masaru Nagisa

A certain class of matrix-valued Borel matrix functions is introduced and it is shown that all functions of that class naturally operate on any operator T in a finite type I von Neumann algebra M in a way such that uniformly bounded…

Operator Algebras · Mathematics 2017-05-26 Piotr Niemiec

Operator convex functions defined on the positive half-line play a prominent role in the theory of quantum information, where they are used to define quantum $f$-divergences. Such functions admit integral representations in terms of…

Optimization and Control · Mathematics 2023-05-23 Oisín Faust , Hamza Fawzi

In this paper, we consider the locally convex spaces of entire functions with growth given by proximate orders, and study the representation as a differential operator of a continuous homomorphism from such a space to another one. As a…

Functional Analysis · Mathematics 2020-03-26 Takashi Aoki , Ryuichi Ishimura , Yasunori Okada

We use a model operator approach and the spectral theorem for self-adjoint operators in a Hilbert space to derive the basic results of abstract left-definite theory in a straightforward manner. The theory is amply illustrated with a variety…

Spectral Theory · Mathematics 2024-08-06 Christoph Fischbacher , Fritz Gesztesy , Paul Hagelstein , Lance Littlejohn

We systematically derive general properties of continuous and holomorphic functions with values in closed operators, allowing in particular for operators with empty resolvent set. We provide criteria for a given operator-valued function to…

Functional Analysis · Mathematics 2015-06-17 Jan Dereziński , Michał Wrochna

We analyze and characterize maximal monotonicity of linear relations (set-valued operators with linear graphs). An important tool in our study are Fitzpatrick functions. The results obtained partially extend work on linear and at most…

Functional Analysis · Mathematics 2008-05-29 Heinz H. Bauschke , Xianfu Wang , Liangjin Yao

The most important open problem in Monotone Operator Theory concerns the maximal monotonicity of the sum of two maximally monotone operators provided that Rockafellar's constraint qualification holds. In this paper, we prove the maximal…

Functional Analysis · Mathematics 2010-10-22 Liangjin Yao

We introduce a notion of completely bounded holomorphic functions defined on the open unit ball of an operator space. We endow the set of these functions with an operator space structure, and in the scalar-valued case we identify an…

Functional Analysis · Mathematics 2024-05-16 Javier Alejandro Chávez-Domínguez , Verónica Dimant

We observe that if f is a continuous function on an interval I and x_0 \in I, then f is operator monotone if and only if the function (f(x) - f(x_0)/(x - x_0) is strongly operator convex. Then starting with an operator monotone function…

Functional Analysis · Mathematics 2017-12-25 Lawrence G. Brown

In studying the complex H\'enon maps, Mummert (in "Holomorphic shadowing for H\'enon maps" Nonlinearity 21 pp. 2887-2898, 2008) defined an operator the fixed points of which give rise to bounded orbits. This enabled him to obtain an…

Dynamical Systems · Mathematics 2022-03-08 Yi-Chiuan Chen

We show that the set of all possible constant diagonals of a bounded Hilbert space operator is always convex. This, in particular, answers an open question of J.-C. Bourin ($2003$). Moreover, we show that the joint numerical range of a…

Functional Analysis · Mathematics 2021-02-16 Vladimir Müller , Yuri Tomilov

In [S. Basu, A. Gabrielov, N. Vorobjov, Semi-monotone sets. arXiv:1004.5047v2 (2011)] we defined semi-monotone sets, as open bounded sets, definable in an o-minimal structure over the reals, and having connected intersections with all…

Logic · Mathematics 2013-04-10 Saugata Basu , Andrei Gabrielov , Nicolai Vorobjov