Connectivity of the adjacency graph of complementary components of the SLE fan

Abstract

Suppose that $h$ is an instance of the Gaussian free field (GFF) on a simply connected domain $D \subseteq {\mathbf C}$ and $x,y \in \partial D$ are distinct. Fix $\kappa \in (0,4)$ and for each $\theta \in {\mathbf R}$ let $\eta_\theta$ be the flow line of $h$ from $x$ to $y$. Recall that for $\theta_1 < \theta_2$ the fan ${\mathbf F}(\theta_1,\theta_2)$ of flow lines of $h$ from $x$ to $y$ is the closure of the union of $\eta_\theta$ as $\theta$ varies in any fixed countable dense subset of $[\theta_1,\theta_2]$. We show that the adjacency graph of components of $D \setminus {\mathbf F}(\theta_1,\theta_2)$ is a.s. connected, meaning it a.s. holds that for every pair $U,V$ of components there exist components $U_1,\ldots,U_n$ so that $U_1 = U$, $U_n = V$, and $\partial U_i \cap \partial U_{i+1} \neq \emptyset$ for each $1 \leq i \leq n-1$. We further show that ${\mathbf F}(\theta_1,\theta_2)$ a.s. determines the flow lines used in its construction. That is, for each $\theta \in [\theta_1,\theta_2]$ we prove that $\eta_\theta$ is a.s. determined by ${\mathbf F}(\theta_1,\theta_2)$ as a set.