Results 1 to 10 of about 513 (80)
Further refinements of some numerical radius inequalities for operators
Operators and Matrices, 2023 . In this work, we give re fi nements of some well-known numerical radius inequalities. Also, we present an improvement of the triangle inequality for the operator norm. Mathematics subject classi fi cation (2020): 47A12, 47A30, 47B15.
Soumia Soltani, Abdelkader Frakis
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Preservers of the c-numerical radius of operator jordan semi-triple products
Operators and Matrices, 2021 Let H be a complex Hilbert space with dimH 3 , let B(H ) be the algebra of all bounded linear operators on H and let Bs(H ) be the real Jordan algebra of all self-adjoint operators in B(H ) . Let A = B(H ) or Bs(H ) .
Y. Zhang, X. Fang
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A Chain of numerical radius inequalities in complex Hilbert space
Journal of Mathematical Inequalities, 2021 In this paper, we implement the improvement of numerical radius inequalities that were produced by Alomari MW. [Refinements of some numerical radius inequalities for Hilbert space operators. Linear and Multilinear Algebra.
Mohammed Al-Dolat +2 more
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Common fixed points for weak commutative mappings on a multiplicative metric space
Fixed Point Theory and Applications, 2014 In this paper, we discuss the unique common fixed point of two pairs of weak commutative mappings on a complete multiplicative metric space. They satisfy the following inequality: d(Sx,Ty)≤{max{d(Ax,By),d(Ax,Sx),d(By,Ty),d(Sx,By),d(Ax,Ty)}}λ, where A and
Xiaoju He, Meimei Song, D. Chen
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Cauchy-Schwarz type inequalities and applications to numerical radius inequalities
, 2020 We present new improvements of certain Cauchy–Schwarz type inequalities. As applications of the results obtained, we provide refinements of some numerical radius inequalities for Hilbert space operators. It is shown, among other inequalities, that if A ∈
F. Kittaneh, H. Moradi
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New norm equalities and inequalities for certain operator matrices
, 2020 We prove new norm equalities and inequalities for general n×n tridiagonal and antitridiagonal operator matrices, including pinching type inequalities for weakly unitarily invariant norms.
Watheq Bani-Domi +2 more
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Some new operator inequalities
, 2020 In this article, we present some new inequalities for positive linear mappings that can be viewed as super multiplicative inequalities. As applications, we deduce some numerical radius inequalities.
M. Sababheh +2 more
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Operator inequalities via geometric convexity
Mathematical Inequalities & Applications, 2019 The main goal of this paper is to present new generalizations of some known inequalities for the numerical radius and unitarily invariant norms of Hilbert space operators.
M. Sababheh, H. Moradi, S. Furuichi
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Operators with minimal pseudospectra and connections to normality
, 2020 This paper mainly studies the class of bounded linear operators A with minimal pseudospectra σε (A) = σ(A)+Dε for some ε > 0 , where σ(A) denotes the spectrum of A , and Dε denotes the open disk of radius ε centered at the origin.
Samir Raouafi
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Topological properties of the block numerical range of operator matrices
, 2020 We show that the block numerical range of an n×n -operator matrix A corresponding to an operator A on the Banach space X with respect to a decomposition X = ∏Xj has at most n connected components.
Agnes Radl, M. Wolff
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