English

Invariant subspace of composition operators on Hardy space

Functional Analysis 2021-01-21 v1 Complex Variables

Abstract

We consider the invariant subspace of composition operators on Hardy space HpH^p where the composition operators corresponding to a function φ\varphi that is a holomorphic self-map of D\mathbb D. Firstly, we discuss composition operators CφC_\varphi on subspace Hα,βpH_{\alpha,\beta}^p of Hardy space HpH^p. We will explore the invariant subspaces for CφC_\varphi in various special cases. Secondly, we consider Beurling type invariant subspace for CφC_\varphi. When θ\theta is a inner function, we prove that θHp\theta H^p is invariant for CφC_\varphi if and only if θφθ\displaystyle{\frac{\theta\circ\varphi}{\theta}} belongs to S(D)\mathcal S(\mathbb D). Thirdly, we obtain that znHpz^nH^p is nontrivial invariant subspace for Deddends algebras DCφ\mathcal D_{C_\varphi} when CφC_\varphi is a compact composition operator and φ\varphi satisfies that φ(0)=0\varphi(0)=0 and φ<1\parallel\varphi\parallel_\infty<1.

Keywords

Cite

@article{arxiv.2101.07944,
  title  = {Invariant subspace of composition operators on Hardy space},
  author = {Tianyu Bai and Junming Liu},
  journal= {arXiv preprint arXiv:2101.07944},
  year   = {2021}
}

Comments

23 pages