Results 31 to 40 of about 528 (95)
Derivations in Banach algebras
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 10, Page 579-583, 2002., 2002 We present some conditions which imply that a derivation on a Banach algebra maps the algebra into its Jacobson radical.
Kyoo-Hong Park +2 more
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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'
semanticscholar +1 more source
Derivations of certain operator algebras
International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 5, Page 345-349, 2000., 2000 Let 𝒩 be a nest and let 𝒜 be a subalgebra of L(H) containing all rank one operators of alg 𝒩. We give several conditions under which any derivation δ from 𝒜 into L(H) must be inner. The conditions include (1) H− ≠ H, (2) 0+ ≠ 0, (3) there is a nontrivial projection in 𝒩 which is in 𝒜, and (4) δ is norm continuous. We also give some pplications.
Jiankui Li, Hemant Pendharkar
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Absolute continuity and hyponormal operators
International Journal of Mathematics and Mathematical Sciences, Volume 4, Issue 2, Page 321-335, 1981., 1981 Let T be a completely hyponormal operator, with the rectangular representation T = A + iB, on a separable Hilbert space. If 0 is not an eigenvalue of T* then T also has a polar factorization T = UP, with U unitary. It is known that A, B and U are all absolutely continuous operators.
C. R. Putnam
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Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2022 In the present paper we introduce a new class of analytic functions f in the open unit disk normalized by f(0) = f′(0)−1 = 0, associated with exponential functions.
Breaz Daniel +2 more
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A NOTE ON P-SYMMETRIC OPERATORS
, 2016 Let L(H) denote the algebra of operators on a complex infinite dimensional Hilbert space H into itself. In this paper, we study the class of operators A ∈ L(H) which satisfy the following property, AT = TA implies AT ∗ = T ∗A for all T ∈ C1(H) (trace ...
S. Bouali +3 more
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Once More on Positive Commutators
, 2012 Let A and B be bounded operators on a Banach lattice E such that the commutator C=AB-BA and the product BA are positive operators. If the product AB is a power-compact operator, then C is a quasi-nilpotent operator having a triangularizing chain of ...
Drnovšek, Roman
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On numerical solution of nonlinear parabolic multicomponent diffusion-reaction problems
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2021 This work continues our previous analysis concerning the numerical solution of the multi-component mass transfer equations. The present test problems are two-dimensional, parabolic, non-linear, diffusion- reaction equations. An implicit finite difference
Juncu Gh., Popa C., Sarbu Gh.
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ON THE MAXIMAL NUMERICAL RANGE OF ELEMENTARY OPERATORS
, 2017 The notion of the numerical range has been generalized in different directions. One such direction, is the maximal numerical range introduced by Stampfli (1970) to derive an identity for the norm of a derivation on L(H). Unlike the other generalizations,
Mati Runji +2 more
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