Results 11 to 20 of about 579 (72)
Concrete Operators, 2022 Let (X, 𝒜, μ) be a σ−finite measure space. A transformation ϕ : X → X is non-singular if μ ∘ ϕ−1 is absolutely continuous with respect with μ. For this non-singular transformation, the composition operator Cϕ: 𝒟(Cϕ) → L2(μ) is defined by Cϕf = f ∘ ϕ, f ∈
Zhou Hang
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On quasi-contractivity of C 0-semigroups on Banach spaces [PDF]
, 2004 A basic result in semigroup theory states that every C-0-semigroup is quasi-contractive with respect to some appropriately chosen equivalent norm. This paper contains a counterpart of this well-known fact.
Matolcsi, Máté
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n-fold Jordan product commuting maps with a λ-Aluthge transform
, 2020 Let B(H) be the set of all bounded linear operators from H to H , where H is a complex Hilbert space. In this paper, we study the properties of T when the λ -Aluthge transform of Tn is T . Also we prove that the bijective map Φ : B(H) →B(K) commutes with
Youn in Kim, Eungil Ko
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Factorization and range inclusion of adjointable operators on the weighted Hilbert C^∗-modules
, 2020 The indefinite inner products induced by invertible and self-adjoint weights are introduced for elements in Hilbert C∗ -modules. The solvability of the equation AX =C is considered for Hilbert C∗ -module operators.
Chunhong Fu +3 more
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On (m, P)-expansive operators: products, perturbation by nilpotents, Drazin invertibility
Concrete Operators, 2021 A generalisation of m-expansive Hilbert space operators T ∈ B(ℋ) [18, 20] to Banach space operators T ∈ B(𝒳) is obtained by defining that a pair of operators A, B ∈ B(𝒳) is (m, P)-expansive for some operator P ∈ B(𝒳) if Δ A,Bm(P)= (I-LARB)m(P)=∑j=0m(-1)j(
Duggal B.P.
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(A,m)-Symmetric commuting tuples of operators on a Hilbert space
Mathematical Inequalities & Applications, 2019 Let T = (T1, · · · ,Td) and A be a commuting d -tuple of operators and a positive operator on a complex Hilbert space, respectively. We introduce an (A,m) -symmetric commuting tuple of operators and characterize the joint approximate point spectrum of (A,
M. Chō, S. Mahmoud
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Essential Self-Adjointness of Anti-Commutative Operators [PDF]
, 2014 In this article, the self-adjoint extensions of symmetric operators satisfying anti-commutation relations are considered. It is proven that an anti-commutative type of the Glimm-Jaffe-Nelson commutator theorem follows.
Takaesu, Toshimitsu
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General numerical radius inequalities for matrices of operators
Open Mathematics, 2016 Let Ai ∈ B(H), (i = 1, 2, ..., n), and T=[0⋯0A1⋮⋰A200⋰⋰⋮An0⋯0] $ T = \left[ {\matrix{ 0 & \cdots & 0 & {A_1 } \cr \vdots & {\mathinner{\mkern2mu\raise1pt\hbox{.}\mkern2mu \raise4pt\hbox{.}\mkern2mu\raise7pt\hbox{.}\mkern1mu}} & {A_2 } & 0
Al-Dolat Mohammed +3 more
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Unitaries Permuting Two Orthogonal Projections [PDF]
, 2017 Let $P$ and $Q$ be two orthogonal projections on a separable Hilbert space, $\calH$. Wang, Du and Dou proved that there exists a unitary, $U$, with $UPU^{-1} =Q, \quad UQU^{-1} = P$ if and only if $\dim(\ker P \cap \ker(1-Q)) = \dim(\ker Q \cap \ker(1-P))
Simon, Barry
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The pseudodifferential operator A(x, D)
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 8, Page 407-419, 2004., 2004 The pseudodifferential operator (p.d.o.) A(x, D), associated with the Bessel operator d2/dx2 + (1 − 4μ2)/4x2, is defined. Symbol class Hρ,δm is introduced. It is shown that the p.d.o. associated with a symbol belonging to this class is a continuous linear mapping of the Zemanian space Hμ into itself. An integral representation of p.d.o.
R. S. Pathak, S. Pathak
wiley +1 more source