Results 1 to 10 of about 12 (12)
Spectrum and Analytic Functional Calculus for Clifford Operators via Stem Functions
Concrete Operators, 2021 The main purpose of this work is the construction of an analytic functional calculus for Clifford operators, which are operators acting on certain modules over Clifford algebras.
Vasilescu Florian-Horia
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Gradient Inequalities for an Integral Transform of Positive Operators in Hilbert Spaces
Annales Mathematicae Silesianae, 2023 For a continuous and positive function w (λ) , λ > 0 and µ a positive measure on (0, ∞) we consider the following integral transform 𝒟(w,μ)(T):=∫0∞w(λ)(λ+T)-1dμ(λ),\mathcal{D}\left( {w,\mu } \right)\left( T \right): = \int_0^\infty {w\left( \lambda ...
Dragomir Silvestru Sever
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Annales Mathematicae Silesianae, 2021 For a continuous and positive function ω (λ); λ> 0 and μ a positive measure on [0; ∞) we consider the following 𝒟-logarithmic integral transform𝒟ℒog(w,μ)(T):=∫0∞w(λ)1n(λ+Tλ)dμ(λ),\mathcal{D}\mathcal{L}og\left( {w,\mu } \right)\left( T \right): = \int_0 ...
Dragomir Silvestru Sever
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On a class of shift-invariant subspaces of the Drury-Arveson space
Concrete Operators, 2018 In the Drury-Arveson space, we consider the subspace of functions whose Taylor coefficients are supported in a set Y⊂ ℕd with the property that ℕ\X + ej ⊂ ℕ\X for all j = 1, . . . , d.
Arcozzi Nicola, Levi Matteo
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The Cayley transform of Banach algebras
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 7, Page 427-428, 2002., 2002 The main result of Haynes (1991) is that a square matrix is convergent (limn→∞Dn = 0) if and only if it is the Cayley transform CA = (I−A)−1(I + A) of a stable matrix A. In this note, we show, with a simple proof, that the above is true in a much more general setting of complex Banach algebras.
Zhidong Pan
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Continuity and general perturbation of the Drazin inverse for closed linear operators
Abstract and Applied Analysis, Volume 7, Issue 6, Page 335-347, 2002., 2002 We study perturbations and continuity of the Drazin inverse of a closed linear operator A and obtain explicit error estimates in terms of the gap between closed operators and the gap between ranges and nullspaces of operators. The results are used to derive a theorem on the continuity of the Drazin inverse for closed operators and to describe the ...
N. Castro González +2 more
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On further refinements for Young inequalities
Open Mathematics, 2018 In this paper sharp results on operator Young’s inequality are obtained. We first obtain sharp multiplicative refinements and reverses for the operator Young’s inequality.
Furuichi Shigeru, Moradi Hamid Reza
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Regularized functional calculi, semigroups, and cosine functions for pseudodifferential operators
Abstract and Applied Analysis, Volume 2, Issue 1-2, Page 121-136, 1997., 1997 Let iAj(1 ≤ j ≤ n) be generators of commuting bounded strongly continuous groups, A ≡ (A1, A2, …, An). We show that, when f has sufficiently many polynomially bounded derivatives, then there exist k, r > 0 such that f(A) has a ‐regularized BCk(f(Rn)) functional calculus.
Ralph Delaubenfels, Yansong Lei
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An Operator Extension of Čebyšev Inequality
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2017 Some operator inequalities for synchronous functions that are related to the čebyšev inequality are given. Among other inequalities for synchronous functions it is shown that ∥ø(f(A)g(A)) - ø(f(A))ø(g(A))∥ ≤ max{║ø(f2(A)) - ø2(f(A))║, ║ø)G2(A)) - ø2(g(A))
Moradi Hamid Reza +2 more
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Fractional powers of non‐negative operators in Fréchet spaces
, 1988 International Journal of Mathematics and Mathematical Sciences, Volume 12, Issue 2, Page 309-320, 1989.
C. Martinez, M. Sanz, V. Calvo
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