Polynomial differentiation composition operators from the minimal Möbius invariant space into Zygmund-type spaces

Source abstract

Abstract We characterize the boundedness and compactness of the polynomial differentiation composition operator P ψ → , φ n {P_{\vec{\psi},\varphi}^{n}} from the minimal Möbius invariant space ℬ 1 {{\mathcal{B}}_{1}} to the Zygmund-type space 𝒵 μ {{\mathcal{Z}}_{\mu}} and its little subspace 𝒵 μ , 0 {{\mathcal{Z}}_{\mu,0}} . Using derivative estimates and test functions in ℬ 1 {{\mathcal{B}}_{1}} , we obtain explicit necessary and sufficient conditions for boundedness, along with asymptotic estimates for the operator norm. We further establish complete compactness criteria. These results complement and improve upon recent studies in this direction.