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Artículo
Strongly compact algebras
(Real Academia de Ciencias Exactas, Fisicas y Naturales, 2006)
An algebra of bounded linear operators on a Hilbert space is said to be strongly compact if its unit ball is relatively compact in the strong operator topology. A bounded linear operator on a Hilbert space is said to be ...
Artículo
Extended eigenvalues of composition operators
(Elsevier, 2021-12-15)
A complex scalar λ is said to be an extended eigenvalue of a bounded linear operator A on a complex Hilbert space if there is a nonzero operator X such that AX=λXA. The results in this paper provide a full solution to the ...
Artículo
Hardy-Littlewood inequalities for norms of positive operators on sequence spaces
(Elsevier, 2013-01-01)
We consider estimates of Hardy and Littlewood for norms of operators on sequence spaces, and we apply a factorization result of Maurey to obtain improved estimates and simplified proofs for the special case of a positive operator.
Artículo
Function algebras with a strongly precompact unit ball
(Elsevier, 2013-10-01)
Let µ be a finite positive Borel measure with compact support K ⊆ C, and regard L∞(µ) as an algebra of multiplication operators on the Hilbert space L2(µ). Then consider the subalgebra A(K) of all continuous functions on ...
Artículo
A local spectral condition for strong compactness with some applications to bilateral weighted shifts
(American Mathematical Society, 2014-01)
An algebra of bounded linear operators on a Banach space is said to be strongly compact if its unit ball is precompact in the strong operator topology, and a bounded linear operator on a Banach space is said to be strongly ...
Artículo
Invariant subspaces and Deddens algebras
(Elsevier, 2015)
It is shown that if the Deddens algebra DT associated with a quasinilpotent operator T on a complex Banach space is closed and localizing then T has a nontrivial closed hyperinvariant subspace.
Artículo
Essential norm of composition operators on Banach spaces of Hölder functions
(2011)
Let (X, d) be a pointed compact metric space, let 0 < α < 1, and let ϕ : X → X be a base point-preserving Lipschitz map. We show that the essential norm of the composition operator Cϕ induced by the symbol ϕ on the ...
Artículo
Extended eigenvalues for Cesàro operators
(Elsevier, 2015-09-15)
A complex scalar λ is said to be an extended eigenvalue of a bounded linear operator T on a complex Banach space if there is a nonzero operator X such that T X = λXT. Such an operator X is called an extended eigenoperator ...
Artículo
Extended eigenvalues of composition operators
(Elsevier, 2021-12-15)
A complex scalar λ is said to be an extended eigenvalue of a bounded linear operator A on a complex Hilbert space if there is a nonzero operator X such that . The results in this paper provide a full solution to the problem ...