Results 31 to 40 of about 604,967 (307)
The block numerical range of analytic operator functions [PDF]
, 2014 We introduce the block numerical range Wn(L) of an operator function L with respect to a decomposition H = H1⊕. . .⊕Hn of the underlying Hilbert space.
Markus Wagenhofer +5 more
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Investigations of the numerical range of a operator matrix
Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2014 We consider a $2\times2$ operator matrix $A$ (so-called generalized Friedrichs model) associated with a system of at most two quantum particles on ${\rm d}$-dimensional lattice.
Tulkin Kh Rasulov, Elyor B Dilmurodov
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Reduction of the c-numerical range to the classical numerical range
Linear Algebra and its Applications, 2011 For an \(n\)-by-\(n\) complex matrix \(A\) and a real \(n\)-tuple \(c=(c_1,\dots, c_n)\), the \(c\)-numerical range \(W_c(A)\) of \(A\) is, by definition, the subset \[ \Biggl\{\sum^n_{j=1} c_j x^*_j Ax_j: x_1,\dots, x_n\text{ form an orthonormal basis of }\mathbb{C}^n\Biggr\} \] of the complex plane.
Chien, Mao-Ting, Nakazato, Hiroshi
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Norm and Numerical Radius Inequalities for a Product of Two Linear Operators in Hilbert Spaces [PDF]
, 2006 The main aim of the present paper is to establish some norm and numerical radius inequalities for the composite operator BA under suitable assumptions for the transform Cα ,β (T) := (T∗ −α I)(β I−T) , where α ,β ∈ C and T ∈ B(H), of the operators ...
S. S. Dragomir +2 more
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On Preserving Properties of Linear Maps on $C^{*}$-algebras [PDF]
Sahand Communications in Mathematical Analysis, 2020 Let $A$ and $B$ be two unital $C^{*}$-algebras and $varphi:A rightarrow B$ be a linear map. In this paper, we investigate the structure of linear maps between two $C^{*}$-algebras that preserve a certain property or relation.
Fatemeh Golfarshchi +1 more
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On generalized numerical ranges [PDF]
Pacific Journal of Mathematics, 1976 which ||(T- viyι\\ = l/d(υ, W(T)), v£ CLW(T), where CLW(T) is the closure of the numerical range W(T) of Γ, has been generalized by using the concept of generalized numerical ranges due to C. S. Lin. Also it has been shown that the notions of generalized Minkowski distance functionals and generalized numerical ranges arise in a natural way for elements
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The numerical range of an operator [PDF]
Pacific Journal of Mathematics, 1970 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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A note on classes of structured matrices with elliptical type numerical range [PDF]
, 2021 summary:We identify new classes of structured matrices whose numerical range is of the elliptical type, that is, an elliptical disk or the convex hull of elliptical ...
Bebiano, Natália, Furtado, Susana
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Spatial numerical ranges of elements of subalgebras of C0(X)
International Journal of Mathematics and Mathematical Sciences, 2000 When A is a subalgebra of the commutative Banach algebra C0(X) of all continuous complex-valued functions on a locally compact Hausdorff space X, the spatial numerical range of element of A can be described in terms of positive measures.
Sin-Ei Takahasi
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Some results on generalized finite operators and range kernel orthogonality in Hilbert spaces
Demonstratio Mathematica, 2021 Let ℋ{\mathcal{ {\mathcal H} }} be a complex Hilbert space and ℬ(ℋ){\mathcal{ {\mathcal B} }}\left({\mathcal{ {\mathcal H} }}) denotes the algebra of all bounded linear operators acting on ℋ{\mathcal{ {\mathcal H} }}.
Mesbah Nadia +2 more
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