Results 271 to 280 of about 382,466 (311)
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q-Numerical radius inequalities for Hilbert space
Linear and multilinear algebra, 2023The aim of this paper is to study the q-numerical radius $ \omega _{q}(.) $ ωq(.) of bounded linear operators on Hilbert spaces. More precisely, first, we show that $ \omega _{q}(.) $ ωq(.) defines a norm which is equivalent to the operator norm.
Sadaf Fakhri Moghaddam +2 more
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Advancement of Numerical Radius Inequalities of Operators and Product of Operators
Iranian Journal of Science, 2023In this article, we prove upper bounds for the numerical radius of bounded linear operator and product of operators, which generalize and improve existing inequalities.
R. Nayak
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Birkhoff–James orthogonality and numerical radius inequalities of operator matrices
Monatshefte für Mathematik (Print), 2019We completely characterize Birkhoff-James orthogonality with respect to numerical radius norm in the space of bounded linear operators on a complex Hilbert space. As applications of the results obtained, we estimate lower bounds of numerical radius for n×
A. Mal, K. Paul, Jeet Sen
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Quadratic operator inequalities and linear-fractional relations
Functional Analysis and Its Applications, 2007Let \(A, B, C\) be bounded Hilbert space operators, and let \(A\) and \(C\) be selfadjoint. Let \(M(A,B,C)\) denote the set of all bounded linear operators \(X\) satisfying the quadratic operator inequality \(X^*AX+B^*X+X^*B+C \leq 0\). Applying the operator \(2\times 2\) matrix \((A;B;B^*;C)\), the authors discuss some set theoretic and topological ...
Khatskevich, V. A. +2 more
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Development of inequalities and characterization of equality conditions for the numerical radius
, 2021Let A be a bounded linear operator on a complex Hilbert space and ℜ ( A ) ( ℑ ( A ) ) denote the real part (imaginary part) of A. Among other refinements of the lower bounds for the numerical radius of A, we prove that w ( A ) ≥ 1 2 ‖ A ‖ + 1 2 | ‖ ℜ ( A
Pintu Bhunia, K. Paul
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Inequalities of Polya type for positive linear operators
Houston journal of mathematics, 1996A number of inequalities are derived for power means and quasi-arithmetic means of bounded linear positive operators on an infinite dimensional Hilbert space.
Mond, B. +3 more
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Some operator inequalities involving operator means and positive linear maps
Linear and Multilinear Algebra, 2017AbstractLet A and B be two positive operators with for positive real numbers be an operator mean and be the adjoint mean of If and is a positive unital linear map, thenwhereand is the Kantorovich constant.
Maryam Khosravi +2 more
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Mixed means inequalities for positive linear operators
Gazette - Australian Mathematical Society, 1996In [3] we raised the question of mixed means for different kind of means. Here we use the concept of connections first introduced by Kubo and Ando to obtain some operator generalizations of mixed - mean inequalities presented in [3].
Mond, B., Pečarić, J. E.
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Golden ratio algorithms for variational inequalities
Mathematical programming, 2018The paper presents a fully adaptive algorithm for monotone variational inequalities. In each iteration the method uses two previous iterates for an approximation of the local Lipschitz constant without running a linesearch.
Yura Malitsky
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Weighted Inequalities for Maximal Operators: Linearization, Localization and Factorization
American Journal of Mathematics, 1986Let \({\mathcal Q}\) be the family of all finite cubes Q in \(R^ n\) with sides parallel to the axes and let \(M_{{\mathcal Q}}\) denote the Hardy-Littlewood maximal operator. According to a fundamental result of Muckenhoupt, \(M_{{\mathcal Q}}\) is a bounded operator on the Lebesgue-space \(L^ p(d\mu ...
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