Results 41 to 50 of about 1,164 (138)
Some Hermite-Hadamard type inequalities for operator convex functions and positive maps
In this paper we establish some inequalities of Hermite-Hadamard type for operator convex functions and positive maps. Applications for power function and logarithm are also provided.
Dragomir S. S.
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Unitarily invariant norm inequalities for operators
We present several norm inequalities for Hilbert space operators. In particular, we prove that if A1,A2,…,An∈B(H), then |||A1A2∗+A2A3∗+⋯+AnA1∗|||⩽∑i=1nAiAi∗for all unitarily invariant norms. We also show that if A1,A2,A3,A4 are projections in B(H), then ∑
M. Erfanian Omidvar+2 more
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Fundamental Hlawka-like inequalities for three and four vectors
We investigate Hlawka-like inequalities for three vectors and determine necessary and sufficient conditions such that a1 3 ∑ i=1 ‖xi‖+a2 ∑ 1 i< j 3 ∥ xi + x j ∥ ∥+a3‖x1 + x2 + x3‖ 0 is satisfied for all x1,x2,x3 in a Hlawka space.
Marius Munteanu
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On approximation properties of some non-positive Bernstein-Durrmeyer type operators
In this paper we shall introduce a new type of Bernstein Durrmeyer operators which are not positive on the entire interval [0, 1]. For these operators we will study the uniform convergence on all continuous functions on [0, 1] as well as a result given ...
Vasian Bianca Ioana
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In this paper we consider some generalizations of the Ando inequality ||| f (A)− f (B)||| ||| f (|A−B|)||| with the “weight” (A−B)p . More precisely, for p 1 such that (−1)p = −1 and for a nonnegative function f on [0,∞) such that f (0) = 0 , we study ...
T. Dinh+3 more
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Sesquilinear version of numerical range and numerical radius
In this paper by using the notion of sesquilinear form we introduce a new class of numerical range and numerical radius in normed space 𝒱, also its various characterizations are given. We apply our results to get some inequalities.
Moradi Hamid Reza+3 more
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Schatten p-norm inequalities related to a characterization of inner product spaces
Let $A_1, ... A_n$ be operators acting on a separable complex Hilbert space such that $\sum_{i=1}^n A_i=0$. It is shown that if $A_1, ... A_n$ belong to a Schatten $p$-class, for some $p>0$, then 2^{p/2}n^{p-1} \sum_{i=1}^n \|A_i\|^p_p \leq \sum_{i,j=1 ...
Hirzallah, O.+2 more
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Operator inequalities related to the Corach--Porta--Recht inequality [PDF]
We prove some refinements of an inequality due to X. Zhan in an arbitrary complex Hilbert space by using some results on the Heinz inequality. We present several related inequalities as well as new variants of the Corach--Porta--Recht inequality. We also
Conde, Cristian+2 more
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A note on lpnorms of weighted mean matrices
We present some results concerning the lpnorms of weighted mean matrices. These results can be regarded as analogues to a result of Bennett concerning weighted Carleman's inequalities. 2000 Mathematics Subject Classification: Primary 47A30.
Peng Gao
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Upper bounds of some matrix operators on binomial and Orlicz-binomial double sequence spaces
In this article, we introduce binomial double sequence space bk(α,β;γ,δ) (1≤k≤∞) and Orlicz-binomial double sequence space bφ(α,β;γ,δ), and obtain certain inclusion results related to these spaces.
Taja Yaying, Bipan Hazarika
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