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Mostrando ítems 1-10 de 18
Artículo
Thin sets of integers in Harmonic analysis and p-stable random Fourier series
(Springer, 2011-06)
We investigate the behavior of some thin sets of integers defined through random trigonometric polynomial when one replaces Gaussian or Rademacher variables by p-stable ones, with 1 < p < 2. We show that in one case this ...
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
Nevanlinna counting function and Carleson function of analytic maps
(Springer, 2011-10)
We show that the maximal Nevanlinna counting function and the Carleson function of analytic self-maps of the unit disk are equivalent, up to constants.
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
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
Compact composition operators on the Dirichlet space and capacity of sets of contact points
(Elsevier, 2013-02-15)
We prove several results about composition operators on the Dirichlet space D⁎. For every compact set K⊆∂D of logarithmic capacity , there exists a Schur function φ both in the disk algebra A(D) and in D⁎ such that the ...
Artículo
Some revisited results about composition operators on Hardy spaces
(European Mathematical Society, 2012)
We generalize, on one hand, some results known for composition operators on Hardy spaces to the case of Hardy-Orlicz spaces HΨ: construction of a “slow” Blaschke product giving a non-compact composition operator on ...
Artículo
On the Muskat problem: global in time results in 2D and 3D
(Johns Hopkins University Press, 2016-12)
This paper considers the three dimensional Muskat problem in the stable regime. We obtain a conservation law which provides an L2 maximum principle for the fluid interface. We also show global in time existence for strong ...
Artículo
Infinitesimal Carleson property for weighted measures induced by analytic self-maps of the unit disk
(Springer, 2013-08)
We prove that, for every α>−1, the pull-back measure φ(Aα) of the measure dAα(z)=(α+1)(1−|z|2)αdA(z), where A is the normalized area measure on the unit disk D, by every analytic self-map φ:D→D is not only an (α+2)-Carleson ...
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 < ∞.