Results 11 to 20 of about 4,538,824 (321)
Improved bounds for the numerical radius via polar decomposition of operators [PDF]
Linear Algebra and its Applications, 2023 Using the polar decomposition of a bounded linear operator $A$ defined on a complex Hilbert space, we obtain several numerical radius inequalities of the operator $A$, which generalize and improve the earlier related ones.
Pintu Bhunia
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Some class of numerical radius peak $n$-linear mappings on $l_p$-spaces
Математичні Студії, 2022 For $n\geq 2$ and a real Banach space $E,$ ${\mathcal L}(^n E:E)$ denotes the space of all continuous $n$-linear mappings from $E$ to itself. Let $$\Pi(E)=\Big\{[x^*, (x_1, \ldots, x_n)]: x^{*}(x_j)=\|x^{*}\|=\|x_j\|=1~\mbox{for}~{j=1, \ldots, n}\Big\}.$$
S. G. Kim
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Numerical radius inequalities and estimation of zeros of polynomials [PDF]
Georgian Mathematical Journal, 2023 Let A be a bounded linear operator defined on a complex Hilbert space and let | A | = ( A * A ) 1 2 {|A|=(A^{*}A)^{\frac{1}{2}}} . Among other refinements of the well-known numerical radius inequality w 2 ( A ) ≤ 1 2 ∥ A * A + A A * ∥ {w^{2}(A)\
Suvendu Jana, Pintu Bhunia, K. Paul
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Schur multiplier operator and matrix inequalities [PDF]
Journal of Mahani Mathematical Research, 2023 In this note we obtain a reverse version of the Haagerup Theorem. In particular, if $ A \in \mathbb{M}_{n}$ has a $ 2\times2- $ principal submatrix as $ \left[ \begin{array}{cc}1& \alpha \\\beta & 1\\\end{array}\right]$ with $ \beta \neq \bar{\alpha ...
Alemeh Sheikhhosseini
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Betterment for estimates of the numerical radii of Hilbert space operators [PDF]
AUT Journal of Mathematics and Computing, 2023 We give several inequalities involving numerical radii $\omega \left( \cdot \right)$ and the usual operator norm $\|\cdot\|$ of Hilbert space operators. These inequalities lead to a considerable improvement in the well-known inequalities\begin{equation*}\
Mohammad Davarpanah, Hamid Moradi
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Some Generalized Euclidean Operator Radius Inequalities
Axioms, 2022 In this work, some generalized Euclidean operator radius inequalities are established. Refinements of some well-known results are provided. Among others, some bounds in terms of the Cartesian decomposition of a given Hilbert space operator are proven.
Mohammad W. Alomari +2 more
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Numerical radius orthogonality in $$C^*$$-algebras [PDF]
Annals of Functional Analysis, 2020 In this paper we characterize the Birkhoff--James orthogonality with respect to the numerical radius norm $v(\cdot)$ in $C^*$-algebras. More precisely, for two elements $a, b$ in a $C^*$-algebra $\mathfrak{A}$, we show that $a\perp_{B}^{v} b$ if and only if for each $ \in [0, 2 )$, there exists a state $ _{_ }$ on $\mathfrak{A}$ such that $| _{_ }
Zamani, Ali, Wójcik, Paweł
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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 ) = sup | ( T x , x )
Furuta, Takayuki, Nakamoto, Ritsuo
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More accurate numerical radius inequalities (I) [PDF]
Linear and Multilinear Algebra, 2019 This article complements our previous work in arXiv:1906 ...
Hamid Reza Moradi, Mohammad Sababheh
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Numerical study of hybrid third order compact scheme for hyperbolic conservation laws
Energy Reports, 2020 In this paper, we present a numerical study to study the capability of the radius of curvature to detect the discontinuous point for hybrid high order schemes.
Indra Wibisono, Yanuar, E.A. Kosasih
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