Entropy numbers of Sobolev embeddings of radial Besov spaces. (Q1873782)

This paper investigates the quality of compact embedding between the radial subspaces of Besov and Triebel-Lizorkin spaces on the Euclidean \(n\)-space \(\mathbb{R}^n\). In particular, with proper definitions, the entropy numbers of Sobolev embeddings of radial Besov spaces are independent of the difference \(s_0-s_1\) as long as the embedding is compact.