Continuity envelopes of spaces of generalised smoothness, entropy and approximation numbers Original Research Article

We study continuity envelopes in spaces of generalised smoothness Bpq(s,Ψ) and Fpq(s,Ψ) and give some new characterisations for spaces Bpq(s,Ψ). The results are applied to obtain sharp asymptotic estimates for approximation numbers of compact embeddings of type id:Bpq(s1,Ψ)(U)→B∞∞s2(U), where np