Weighted approximation in higher-dimensional missing digit sets

Abstract

In this note, we use the mass transference principle for rectangles, recently obtained by Wang and Wu (Math. Ann., 2021), to study the Hausdorff dimension of sets of "weighted $\Psi$-well-approximable" points in certain self-similar sets in $\mathbb{R}^{d}$. Specifically, we investigate weighted $\Psi$-well-approximable points in "missing digit" sets in $\mathbb{R}^{d}$. The sets we consider are natural generalisations of Cantor-type sets in $\mathbb{R}$ to higher dimensions and include, for example, four corner Cantor sets (or Cantor dust) in the plane with contraction ratio $\frac{1}{n}$ with $n \in \mathbb{N}$.