English

H\"older conditions and $\tau$-spikes for analytic Lipschitz functions

Functional Analysis 2021-08-06 v1 Complex Variables

Abstract

Let UU be an open subset of C\mathbb{C} with boundary point x0x_0 and let Aα(U)A_{\alpha}(U) be the space of functions analytic on UU that belong to lipα(U)\alpha(U), the "little Lipschitz class". We consider the condition S=n=12(t+λ+1)nM1+α(AnU)<,S= \displaystyle \sum_{n=1}^{\infty}2^{(t+\lambda+1)n}M_*^{1+\alpha}(A_n \setminus U)< \infty, where tt is a non-negative integer, 0<λ<10<\lambda<1, M1+αM_*^{1+\alpha} is the lower 1+α1+\alpha dimensional Hausdorff content, and An={z:2n1<zx0<2n}A_n = \{z: 2^{-n-1}<|z-x_0|<2^{-n}\}. This is similar to a necessary and sufficient condition for bounded point derivations on Aα(U)A_{\alpha}(U) at x0x_0. We show that S=S= \infty implies that x0x_0 is a (t+λ)(t+\lambda)-spike for Aα(U)A_{\alpha}(U) and that if S<S<\infty and UU satisfies a cone condition, then the tt-th derivatives of functions in Aα(U)A_{\alpha}(U) satisfy a H\"older condition at x0x_0 for a non-tangential approach.

Keywords

Cite

@article{arxiv.2002.07158,
  title  = {H\"older conditions and $\tau$-spikes for analytic Lipschitz functions},
  author = {Stephen Deterding},
  journal= {arXiv preprint arXiv:2002.07158},
  year   = {2021}
}

Comments

16 pages, 1 figure. arXiv admin note: text overlap with arXiv:1811.11370