Some numerical radius inequalities for power series of operators in Hilbert spaces [PDF]
Journal of Inequalities and Applications, 2013 By the help of power series f(z)=∑n=0∞anzn, we can naturally construct another power series that has as coefficients the absolute values of the coefficients of f, namely, fa(z):=∑n=0∞|an|zn. Utilizing these functions, we show among others that
S. Dragomir
semanticscholar +4 more sources
Study on Birkhoff orthogonality and symmetry of matrix operators
Open Mathematics, 2023 We focus on the problem of generalized orthogonality of matrix operators in operator spaces. Especially, on ℬ(l1n,lpn)(1≤p≤∞){\mathcal{ {\mathcal B} }}\left({l}_{1}^{n},{l}_{p}^{n})\left(1\le p\le \infty ), we characterize Birkhoff orthogonal elements of
Wei Yueyue, Ji Donghai, Tang Li
doaj +1 more source
Applications of Kato’s inequality for n-tuples of operators in Hilbert spaces, (I)
Journal of Inequalities and Applications, 2013 In this paper, by the use of the famous Kato’s inequality for bounded linear operators, we establish some inequalities for n-tuples of operators and apply them for functions of normal operators defined by power series as well as for some norms and ...
S. Dragomir, Y. Cho, Young-Ho Kim
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Some Jensen's Type Inequalities for Twice Differentiable Functions of Selfadjoint Operators in Hilbert Spaces [PDF]
, 2008 Some Jensen’s type inequalities for twice differentiable functions of selfadjoint operators in Hilbert spaces under suitable assumptions for the involved operators are given.
Dragomir, Sever S
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Invariant manifolds of hypercyclic vectors for the real scalar case [PDF]
, 1999 We show that every hypercyclic operator on a real locally convex vector space admits a dense invariant linear manifold of hypercyclic vectors. Given a locally convex vector space X and a continuous operator T : X -> X, we say that T is hypercyclic ...
J. Bes
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Norm inequalities of Čebyšev type for power series in Banach algebras
Journal of Inequalities and Applications, 2014 Let f(λ)=∑n=0∞αnλn be a function defined by power series with complex coefficients and convergent on the open disk D(0,R)⊂C, R>0 and x,y∈B, a Banach algebra, with xy=yx.
S. Dragomir +3 more
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On Pompeiu-Cebysev type inequalities for positive linear maps of selfadjoint operators in inner product spaces [PDF]
, 2018 In this work, generalizations of some inequalities for continuous $h$-synchronous ($h$-asynchronous) functions of linear bounded selfadjoint operators under positive linear maps in Hilbert spaces are proved.Comment: 12 pages.
Alomari, Mohammad W.
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Trace inequalities of Shisha-Mond type for operators in Hilbert spaces
Concrete Operators, 2017 Some trace inequalities of Shisha-Mond type for operators in Hilbert spaces are provided. Applications in connection to Grüss inequality and for convex functions of selfadjoint operators are also given.
Dragomir Sever Silvestru
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Isometries on extremely non-complex Banach spaces [PDF]
, 2010 Given a separable Banach space $E$, we construct an extremely non-complex Banach space (i.e. a space satisfying that $\|Id + T^2\|=1+\|T^2\|$ for every bounded linear operator $T$ on it) whose dual contains $E^*$ as an $L$-summand.
Koszmider, Piotr +2 more
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Strictly singular operators and isomorphisms of Cartesian products of power series spaces [PDF]
, 1998 V. P. Zahariuta, in 1973, used the theory of Fredholm operators to develop a method to classify Cartesian products of locally convex spaces. In this work we modify his method to study the isomorphic classification of Cartesian products of the kind E0p(a)×
Djakov, Plamen Borissov +5 more
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