On homogeneous Sobolev and Besov spaces on the whole and the half space
arXiv:2211.07707 · doi:10.2140/tunis.2024.6.343
Abstract
In this paper, we propose an elementary construction of homogeneous Sobolev spaces of fractional order on and . This construction completes the construction of homogeneous Besov spaces on started by Bahouri, Chemin and Danchin on . We will also extend the treatment done by Danchin and Mucha on , and the construction of homogeneous Sobolev spaces of integer orders started by Danchin, Hieber, Mucha and Tolksdorf on and . Properties of real and complex interpolation, duality, and density are discussed. Trace results are also reviewed. Our approach relies mostly on interpolation theory and yields simpler proofs of some already known results in the case of Besov spaces. The lack of completeness on the whole scale will lead to consideration of intersection spaces with decoupled estimates to circumvent this issue. As standard and simple applications, we treat the problems of Dirichlet and Neumann Laplacians in these homogeneous functions spaces.
Less typos, reorganization of many sections and its contents, some proofs have been more detailed, new appendix.Published in Tunisian Journal of Mathematics, Vol. 6 (2024), No. 2, 343--404, DOI: 10.2140/tunis.2024.6.343 Formatting changes for the published version were not added, be careful with the numbering of sections and subsections