Uncentered Fractional Maximal functions and mean oscillation spaces associated with dyadic Hausdorff content

Abstract: We study the action of uncentered fractional maximal functions on mean oscillation spaces associated with the dyadic Hausdorff content $\mathcal{H}{\infty}^{\beta}$ with $0<\beta\leq n$. For $0 < \alpha < n$, we refine existing results concerning the action of the Euclidean uncentered fractional maximal function $\mathcal{M}{\alpha}$ on the functions of bounded mean oscillations (BMO) and vanishing mean oscillations (VMO). In addition, for $0 < \beta_1 \leq \beta_2 \leq n$, we establish the boundedness of the $\beta_2$-dimensional uncentered maximal function $\mathcal{M}^{\beta_2}$ on the space $\text{BMO}^{\beta_1}(\mathbb{R}^n)$, where $\text{BMO}^{\beta_1}(\mathbb{R}^n)$ denotes the mean oscillation space adapted to the dyadic Hausdorff content $\mathcal{H}_{\infty}^{\beta_1}$ on $\mathbb{R}^n$.