4 citations · 9 across the 9 of their papers we have counts for
10 papers
A unified approach to inequalities for K-functionals and moduli of smoothness
Amiran Gogatishvili, Bohumir Opic, Sergey Tikhonov +1
The paper provides a detailed study of crucial inequalities for smoothness and interpolation characteristics in rearrangement invariant Banach function spaces. We present a unified…
Embeddings for spaces of Lorentz-Sobolev type
Andreas Seeger, Walter Trebels
The purpose of this paper is to characterize all embeddings for versions of Besov and Triebel-Lizorkin spaces where the underlying Lebesgue space metric is replaced by a Lorentz sp…
Low regularity classes and entropy numbers
Andreas Seeger, Walter Trebels
We note a sharp embedding of the Besov space $B^\infty_{0,q}(\bbT)$ into exponential classes and prove entropy estimates for the compact embedding of subclasses with logarithmic sm…
Hankel Multipliers And Transplantation Operators
Krzysztof Stempak, Walter Trebels
Connections between Hankel transforms of different order for -functions are examined. Well known are the results of Guy [Guy] and Schindler [Sch]. Further relations result fro…
Ultraspherical multipliers revisited
George Gasper, Walter Trebels
Sufficient ultraspherical multiplier criteria are refined in such a way that they are comparable with necessary multiplier conditions. Also new necessary conditions for Jacobi mult…
A Riemann--Lebesgue lemma for Jacobi expansions
George Gasper, Walter Trebels
A Lemma of Riemann--Lebesgue type for Fourier--Jacobi coefficients is derived. Via integral representations of Dirichlet--Mehler type for Jacobi polynomials its proof directly redu…
On a restriction problem of de Leeuw type for Laguerre multipliers
George Gasper, Walter Trebels
In 1965 K. de Leeuw \cite{deleeuw} proved among other things in the Fourier transform setting: {\it If a continuous function on generates a bounde…
Fractional integration for Laguerre expansions
George Gasper, Krzysztof Stempak, Walter Trebels
The aim of this note is to provide a fractional integration theorem in the framework of Laguerre expansions. The method of proof consists of establishing an asymptotic estimate for…
On necessary multiplier conditions for Laguerre expansions
George Gasper, Walter Trebels
The necessary multiplier conditions for Laguerre expansions derived in Gasper and Trebels \cite{laguerre} are supplemented and modified. This allows us to place Markett's Cohen typ…
On weighted transplantation and multipliers for Laguerre expansions
Krzysztof Stempak, Walter Trebels
Using the standard square--function method (based on the Poisson semigroup), multiplier conditions of Hörmander type are derived for Laguerre expansions in --spaces with power…