Results 1 to 10 of about 100,077 (295)
Further results on A-numerical radius inequalities [PDF]
Annals of Functional Analysis, 2021 Let A be a bounded linear positive operator on a complex Hilbert space [Formula: see text] Furthermore, let [Formula: see text] denote the set of all bounded linear operators on [Formula: see text] whose A-adjoint exists, and [Formula: see text] signify a diagonal operator matrix with diagonal entries are A.
Rout N, Mishra D.
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A convex treatment of numerical radius inequalities
Linear Algebra and its Applications, 2022 In this article, we prove an inner product inequality for Hilbert space operators. This inequality, then, is utilized to present a general numerical radius inequality using convex functions.
Heydarbeygi, Zahra +3 more
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Annals of Functional Analysis, 2021 The authors introduce the so-called weighted numerical radius of Hilbert space operators and establish many permanence properties of such radius.
Alemeh Sheikhhosseini +2 more
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The decomposable numerical radius and numerical radius of a compound matrix
Linear Algebra and its Applications, 1986 Let A be an n × n complex matrix with singular values α1 ⩾ α2 ⩾ ⋯ ⩾ αn and eigenvalues λ1, λ2,…,λn, where |λ1| ⩾ |λ2| ⩾ ⋯ ⩾ |λn|. Denote by Cm (A) (1 ⩽ m ⩽ n) the mth compound of A, and by ⋀mCn the mth Grassmann space over Cn, in which the elements are ...
Li, Chi-Kwong
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Minimal projections with respect to numerical radius [PDF]
, 2016 In this paper we survey some results on minimality of projections with respect to numerical radius. We note that in the cases Lp, p = 1, 2, ∞, there is no difference between the minimality of projections measured either with respect to operator norm or ...
Asuman Güven Aksoy +3 more
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Refinements of A-numerical radius inequalities and their applications [PDF]
Advances in Operator Theory, 2020 We present sharp lower bounds for the A-numerical radius of semi-Hilbertian space operators. We also present an upper bound. Further we compute new upper bounds for the $B$-numerical radius of $2 \times 2$ operator matrices where $B = \textit{diag}(A,A)$, $A$ being a positive operator. As an application of the A-numerical radius inequalities, we obtain
Pintu Bhunia +2 more
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Euclidean operator radius and numerical radius inequalities
Operators and Matrices, 2023 Let $T$ be a bounded linear operator on a complex Hilbert space $\mathscr{H}.$ We obtain various lower and upper bounds for the numerical radius of $T$ by developing the Euclidean operator radius bounds of a pair of operators, which are stronger than the
Paul, Kallol +2 more
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Journal of Mathematical Analysis and Applications, 2010 In this work we introduce the concept of convex numerical radius for a continuous and linear operator in a Banach space, which generalizes that of the classical numerical radius.
Ruiz Galán, Manuel
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Certain numerical radius contraction operators [PDF]
Proceedings of the American Mathematical Society, 1971 In this paper an operator T means a bounded linear operator on a complex Hilbert space H. The numerical radius norm w ( T ) w(T) of an operator T, is defined by w ( T )
Ritsuo Nakamoto, Takayuki Furuta
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Polarization constant for numerical radius
Mediterranean Journal of Mathematics, 2020 We introduce and investigate the m-th polarization constant of a Banach space X for the numerical radius. We first show the difference between this constant and the original m-th polarization constant associated to the norm by proving that the new ...
García, Domingo +4 more
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