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Mostrando ítems 1-9 de 9
Artículo
A spectral radius type formula for approximation numbers of composition operators
(Elsevier, 2014-12-15)
For approximation numbers an(Cφ) of composition operators Cφ on weighted analytic Hilbert spaces, including the Hardy, Bergman and Dirichlet cases, with symbol φ of uniform norm <1, we prove that limn→∞[an(Cφ)]1/n=e−1 ...
Artículo
Compactification, and beyond, of composition operators on Hardy spaces by weights
(OJS/PKP, 2021-06-08)
We study when multiplication by a weight can turn a non-compact composition operator on H2 into a compact operator, and when it can be in Schatten classes. The q-summing case in Hp is considered. We also study when this ...
Artículo
Comparison of singular numbers of composition operators on different Hilbert spaces of analytic functions
(Elsevier, 2021)
We compare the rate of decay of singular numbers of a given composition operator acting on various Hilbert spaces of analytic functions on the unit disk D. We show that for the Hardy and Bergman spaces, our results are ...
Artículo
Some new properties of composition operators associated with lens maps
(Springer, 2013-05)
We give examples of results on composition operators connected with lens maps. The first two concern the approximation numbers of those operators acting on the usual Hardy space H2. The last ones are connected with ...
Artículo
Approximation numbers of weighted composition operators
(Elsevier, 2018)
We study the approximation numbers of weighted composition operators f 7→ w · (f ◦ ϕ) on the Hardy space H2 on the unit disc. For general classes of such operators, upper and lower bounds on their approximation numbers ...
Artículo
Approximation numbers of composition operators on the Hardy space of the infinite polydisk
(Springer, 2017-12)
We study the composition operators of the Hardy space on D∞ ∩ℓ1, the ℓ1 part of the infinite polydisk, and the behavior of their approximation numbers.
Artículo
Approximation numbers of composition operators on Hp
(De Gruyter Open, 2015-01)
We give estimates for the approximation numbers of composition operators on the Hp spaces, 1 ≤ p < ∞.
Artículo
Two results on composition operators on the Dirichlet space
(Elsevier, 2015-06-15)
We show that the decay of approximation numbers of compact composition operators on the Dirichlet space D can be as slow as we wish. We also prove the optimality of a result of O. El-Fallah, K. Kellay, M. Shabankhah ...
Artículo
Approximation numbers of composition operators on the Dirichlet space
(Springer, 2015-04)
We study the decay of approximation numbers of compact composition operators on the Dirichlet space. We give upper and lower bounds for these numbers. In particular, we improve on a result of O. El-Fallah, K. Kellay, M. ...