Results 31 to 40 of about 601 (93)
On k-quasi-M-hyponormal operators
, 2013 In this present article we introduce a new class of operators which we will be called the class of k -quasi-M -hyponormal operators that includes hyponormal an M -hyponormal operators.
S. Mécheri
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Geometric properties of composition operators belonging to Schatten classes
International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 4, Page 239-248, 2001., 2001 We investigate the connection between the geometry of the image domain of an analytic function mapping the unit disk into itself and the membership of the composition operator induced by this function in the Schatten classes. The purpose is to provide solutions to Lotto′s conjectures and show a new compact composition operator which is not in any of ...
Yongsheng Zhu
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Strongly Lipschitz up-Nuclear Operators
Moroccan Journal of Pure and Applied Analysis, 2019 In this paper, we introduce the notion of strongly Lipschitz up-nuclear operators. Among other results, we prove an analog of the factorization theorem for these classes and characterize their conjugates.
Belacel Amar, Bey Khedidja
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Putnam‐Fuglede theorem and the range‐kernel orthogonality of derivations
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 9, Page 573-582, 2001., 2001 Let ℬ(H) denote the algebra of operators on a Hilbert space H into itself. Let d = δ or Δ, where δAB : ℬ(H) → ℬ(H) is the generalized derivation δAB(S) = AS − SB and ΔAB : ℬ(H) → ℬ(H) is the elementary operator ΔAB(S) = ASB − S. Given A, B, S ∈ ℬ(H), we say that the pair (A, B) has the property PF(d(S)) if dAB(S) = 0 implies dA∗B∗(S)=0.
B. P. Duggal
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A bound for the Hilbert-Schmidt norm of generalized commutators of nonself-adjoint operators
, 2017 Let A, à and B be bounded linear operators in a Hilbert space, and f (z) be a function regular on the convex hull of the union of the spectra of A and à . Let SN2 be the ideal of Hilbert-Schmidt operators.
M. Gil'
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(r, p)‐absolutely summing operators on the space C (T, X) and applications
Abstract and Applied Analysis, Volume 6, Issue 5, Page 309-315, 2001., 2001 We give necessary and sufficient conditions for an operator on the space C (T, X) to be (r, p)‐absolutely summing. Also we prove that the injective tensor product of an integral operator and an (r, p)‐absolutely summing operator is an (r, p)‐absolutely summing operator.
Dumitru Popa
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Bounded sets in the range of an X∗∗‐valued measure with bounded variation
International Journal of Mathematics and Mathematical Sciences, Volume 23, Issue 1, Page 21-30, 2000., 2000 Let X be a Banach space and A ⊂ X an absolutely convex, closed, and bounded set. We give some sufficient and necessary conditions in order that A lies in the range of a measure valued in the bidual space X∗∗ and having bounded variation. Among other results, we prove that X∗ is a G.
B. Marchena, C. Piñeiro
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Open Mathematics, 2019 Let E be a generalized Cesáro sequence space defined by weighted means and by using s-numbers of operators from a Banach space X into a Banach space Y.
Bakery Awad A., Mohammed Mustafa M.
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On Hankel-type operators with discontinuous symbols in higher dimensions [PDF]
Bulletin London Mathematical Society Volume 44 (2012) Issue 3 Pp.
496-502, 2011 We obtain an asymptotic formula for the counting function of the discrete spectrum for Hankel-type pseudo-differential operators with discontinuous symbols.
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On Hilbert-Schmidt compatibility
, 2013 Guided by important examples of differential operators, we obtain sufficient conditions for Hilbert-Schmidt compatibility of operators and apply these conditions in spectral perturbation theory. Mathematics subject classification (2010): 47A55, 47B10.
D. Potapov, A. Skripka, F. Sukochev
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