Results 1 to 10 of about 770,616 (284)
Numerical Radius and Operator Norm Inequalities
Journal of Inequalities and Applications, 2009 A general inequality involving powers of the numerical radius for sums and products of Hilbert space operators is given. This inequality generalizes several recent inequalities for the numerical radius, and includes that if and are operators on a ...
Albadawi Hussien, Shebrawi Khalid
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Scalar field configurations supported by charged compact reflecting stars in a curved spacetime
Physics Letters B, 2018 We study the system of static scalar fields coupled to charged compact reflecting stars through both analytical and numerical methods. We enclose the star in a box and our solutions are related to cases without box boundaries when putting the box far ...
Yan Peng
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Numerical radius inequalities for Hilbert $C^*$-modules [PDF]
Mathematica Bohemica, 2022 We present a new method for studying the numerical radius of bounded operators on Hilbert $C^*$-modules. Our method enables us to obtain some new results and generalize some known theorems for bounded operators on Hilbert spaces to bounded adjointable ...
Sadaf Fakri Moghaddam +1 more
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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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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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Further Accurate Numerical Radius Inequalities
Axioms, 2023 The goal of this study is to refine some numerical radius inequalities in a novel way. The new improvements and refinements purify some famous inequalities pertaining to Hilbert space operators numerical radii.
Tariq Qawasmeh +4 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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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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Further numerical radius inequalities
Journal of Mathematical Inequalities, 2022 In this article, we present some new inequalities for the numerical radius of products of Hilbert space operators and the generalized Aluthge transform. In particular, we show some upper bounds for $ω(ABC+DEF)$ using the celebrated Buzano inequality, then some consequences that generalize some results from the literature are discussed.
Sababheh, Mohammad +2 more
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