Compactness of the Hardy-Littlewood operator on some spaces of harmonic functions.
Comparison of the classical BMO with the BMO spaces associated with operators and applications.
Comparison of wavelet approximation order in different smoothness spaces.
Complete interpolating sequences for Paley-Wiener spaces and Muckenhoupt's (Ap) condition.
We describe the complete interpolating sequences for the Paley-Wiener spaces Lπp (1 < p < ∞) in terms of Muckenhoupt's (Ap) condition. For p = 2, this description coincides with those given by Pavlov [9], Nikol'skii [8] and Minkin [7] of the unconditional bases of complex exponentials in L2(-π,π). While the techniques of these authors are linked to the Hilbert space geometry of Lπ2, our method of proof is based in turning the problem into one about boundedness of the Hilbert transform...
Completely continuous multipliers from into
For a locally compact Hausdorff group we investigate what functions in give rise to completely continuous multipliers from into . In the case of a metrizable group we obtain a complete description of such functions. In particular, for compact all in induce completely continuous .
Completeness in L1(R) of discrete translates.
We characterize, in terms of the Beurling-Malliavin density, the discrete spectra Λ ⊂ R for which a generator exists, that is a function φ ∈ L1(R) such that its Λ translates φ(x - λ), λ ∈ Λ, span L1(R). It is shown that these spectra coincide with the uniqueness sets for certain analytic clases. We also present examples of discrete spectra Λ ∈ R which do not admit a single generator while they admit a pair of generators.
Complex and distributional weights for sieved ultraspherical polynomials.
Complex Hadamard matrices and the spectral set conjecture.
By analyzing the connection between complex Hadamard matrices and spectral sets, we prove the direction "spectral ⇒ tile" of the Spectral Set Conjecture, for all sets A of size |A| ≤ 5, in any finite Abelian group. This result is then extended to the infinite grid Zd for any dimension d, and finally to Rd.
Complex Interpolation and Fourier Multipliers for the Spaces B.... and F.... of Besov-Hardy-Sobolev Type: The Case 0<p....., 0<q.... .
Complex interpolation for Banach spaces
Complex interpolation of function spaces with general weights
We present the complex interpolation of Besov and Triebel–Lizorkin spaces with generalized smoothness. In some particular cases these function spaces are just weighted Besov and Triebel–Lizorkin spaces. As a corollary of our results, we obtain the complex interpolation between the weighted Triebel–Lizorkin spaces and with suitable assumptions on the parameters and , and the pair of weights .
Complex powers and asymptotic expansions. I. Functions of certain types.
Complex powers and asymptotic expansions. II.
Complex Unconditional Metric Approximation Property for spaces
We study the Complex Unconditional Metric Approximation Property for translation invariant spaces of continuous functions on the circle group. We show that although some “tiny” (Sidon) sets do not have this property, there are “big” sets Λ for which has (ℂ-UMAP); though these sets are such that contains functions which are not continuous, we show that there is a linear invariant lifting from these spaces into the Baire class 1 functions.
Comportement à l'infini de certaines fonctions moyenne-périodiques
Comportement asymptotique dans l'algorithme de transformée en ondelettes. Lien avec la régularité de l'ondelette.
We study the asymptotic performance for a Wavelets Transform, in particular as a function of the regularity order of the wavelet.
Comportement local des fonctions à série de Fourier lacunaire
Composition of maximal operators.
Composition operators in the Dirichlet series setting
In this work, we begin with a survey of composition operators on the Hardy space H² and on the Wiener algebra A⁺ of absolutely convergent Taylor series, with special emphasis on their compactness, or invertibility, or isometric character. The main results are due respectively to J. Shapiro and D.~Newman. In a second part, we present more recent results, due to Gordon and Hedenmalm on the one hand, and to Bayart, the author et al. on the other hand, concerning the analogues of H² and A⁺ in the setting...
Composition theorems of Stepanov almost periodic functions and Stepanov-like pseudo-almost periodic functions.