Homogeneous Besov Spaces on Stratified Lie Groups and Their Wavelet Characterization

We establish wavelet characterizations of homogeneous Besov spaces on stratified Lie groups, both in terms of continuous and discrete wavelet systems. We first introduce a notion of homogeneous Besov space B˙p,qs in terms of a Littlewood-Paley-type decomposition, in analogy to the well-known charact...

Full description

Bibliographic Details
Main Authors: Hartmut Führ, Azita Mayeli
Format: Article
Language:English
Published: Hindawi Limited 2012-01-01
Series:Journal of Function Spaces and Applications
Online Access:http://dx.doi.org/10.1155/2012/523586
Description
Summary:We establish wavelet characterizations of homogeneous Besov spaces on stratified Lie groups, both in terms of continuous and discrete wavelet systems. We first introduce a notion of homogeneous Besov space B˙p,qs in terms of a Littlewood-Paley-type decomposition, in analogy to the well-known characterization of the Euclidean case. Such decompositions can be defined via the spectral measure of a suitably chosen sub-Laplacian. We prove that the scale of Besov spaces is independent of the precise choice of Littlewood-Paley decomposition. In particular, different sub-Laplacians yield the same Besov spaces. We then turn to wavelet characterizations, first via continuous wavelet transforms (which can be viewed as continuous-scale Littlewood-Paley decompositions), then via discretely indexed systems. We prove the existence of wavelet frames and associated atomic decomposition formulas for all homogeneous Besov spaces B˙p,qs with 1≤p,q<∞ and s∈ℝ.
ISSN:0972-6802
1758-4965