Some new characterizations of BLO and Campanato spaces in the Schr\"{o}dinger setting

Abstract

Let us consider the Schr\"{o}dinger operator $\mathcal{L}=-\Delta+V$ on $\mathbb R^d$ with $d\geq3$, where $\Delta$ is the Laplacian operator on $\mathbb R^d$ and the nonnegative potential $V$ belongs to certain reverse H\"{o}lder class $RH_s$ with $s\geq d/2$. In this paper, the authors first introduce two kinds of function spaces related to the Schr\"{o}dinger operator $\mathcal{L}$. A real-valued function $f\in L^1_{\mathrm{loc}}(\mathbb R^d)$ belongs to the (BLO) space $\mathrm{BLO}_{\rho,\theta}(\mathbb R^d)$ with $0\leq\theta<\infty$ if \begin{equation*} \|f\|_{\mathrm{BLO}_{\rho,\theta}} :=\sup_{\mathcal{Q}}\bigg(1+\frac{r}{\rho(x_0)}\bigg)^{-\theta}\bigg(\frac{1}{|Q(x_0,r)|} \int_{Q(x_0,r)}\Big[f(x)-\underset{y\in\mathcal{Q}}{\mathrm{ess\,inf}}\,f(y)\Big]\,dx\bigg), \end{equation*} where the supremum is taken over all cubes $\mathcal{Q}=Q(x_0,r)$ in $\mathbb R^d$, $\rho(\cdot)$ is the critical radius function in the Schr\"{o}dinger context. For $0<\beta<1$, a real-valued function $f\in L^1_{\mathrm{loc}}(\mathbb R^d)$ belongs to the (Campanato) space $\mathcal{C}^{\beta,\ast}_{\rho,\theta}(\mathbb R^d)$ with $0\leq\theta<\infty$ if \begin{equation*} \|f\|_{\mathcal{C}^{\beta,\ast}_{\rho,\theta}} :=\sup_{\mathcal{B}}\bigg(1+\frac{r}{\rho(x_0)}\bigg)^{-\theta} \bigg(\frac{1}{|B(x_0,r)|^{1+\beta/d}}\int_{B(x_0,r)}\Big[f(x)-\underset{y\in\mathcal{B}}{\mathrm{ess\,inf}}\,f(y)\Big]\,dx\bigg), \end{equation*} where the supremum is taken over all balls $\mathcal{B}=B(x_0,r)$ in $\mathbb R^d$. Then we establish the corresponding John--Nirenberg inequality suitable for the space $\mathrm{BLO}_{\rho,\theta}(\mathbb R^d)$ with $0\leq\theta<\infty$ and $d\geq3$. Moreover, we give some new characterizations of the BLO and Campanato spaces related to $\mathcal{L}$ on weighted Lebesgue spaces, which is the extension of some earlier results.