Results 21 to 30 of about 100,077 (295)
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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Weighted Inequalities For The Numerical Radius [PDF]
Vietnam Journal of Mathematics, 2021 In this article, we obtain several new weighted bounds for the numerical radius of a Hilbert space operator. The significance of the obtained results is the way they generalize many existing results in the literature; where certain values of the weights imply some known results, or refinements of these results.
Shiva Sheybani +2 more
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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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AIMS Mathematics, 2022 Abstract We give several sharp inequalities involving powers of the numerical radii and the usual operator norms of Hilbert space operators. These inequalities , which are based on some classical convexity inequalities for nonneg-ative real numbers and some operator inequalities, generalize earlier numerical radius inequalities.
M. H. M. Rashid, Feras Bani-Ahmad
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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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New estimates for the numerical radius
Filomat, 2021 In this article, we present new inequalities for the numerical radius of the sum of two Hilbert space operators. These new inequalities will enable us to obtain many generalizations and refinements of some well known inequalities, including multiplicative behavior of the numerical radius and norm bounds. Among many other applications, it is
Moradi, Hamid Reza, Sababheh, Mohammad
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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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Algorithms, 2022 In this work, some new inequalities for the numerical radius of block n-by-n matrices are presented. As an application, the bounding of zeros of polynomials using the Frobenius companion matrix partitioned by the Cartesian decomposition method is proved.
Mohammad W. Alomari, Christophe Chesneau
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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 $θ\in [0, 2π)$, there exists a state $φ_{_θ}$ on $\mathfrak{A}$ such that $|φ_{_θ}(a)| =
Zamani, Ali, Wójcik, Paweł
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Gap Between Operator Norm and Spectral Radius for the Square of Antidiagonal Block Operator Matrices
Communications in Advanced Mathematical Sciences, 2022 In this work, the gap between operator norm and spectral radius for the square of antidiagonal block operator matrices in the direct sum of Banach spaces has been investigated, and also the gap between operator norm and numerical radius for the square of
Elif Otkun Çevik
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