Critical percolation on the discrete torus in high dimensions
Arthur Blanc-Renaudie, Asaf Nachmias
TL;DR
This work establishes a precise mean-field scaling limit for critical percolation on high-dimensional discrete tori, showing that the largest clusters, properly rescaled, converge to Aldous’s Z_λ limit from critical Erdős–Rényi graphs. The authors develop a two-layer coupling framework, comprising a multiplicative component graph and a sprinkled graph, and prove a six-step contraction that forces the interaction matrix to behave essentially as rank one near criticality. Central to the argument are sharp susceptibility and moment bounds on the infinite lattice Z^d, extended to the torus, and an extended k-arm IIC construction that provides the needed fine-grained control of near-critical clusters. The results connect finite-volume torus percolation to the canonical Erdős–Rényi scaling window, demonstrating a robust mean-field universality in high dimensions and laying groundwork for future GHP-type limits of component-structure objects on finite graphs.
Abstract
We consider percolation on the discrete torus $\mathbb{Z}_n^d$ at $p_c(\mathbb{Z}^d)$, the critical value for percolation on the corresponding infinite lattice $\mathbb{Z}^d$, and within the scaling window around it. We assume that $d$ is a large enough constant for the nearest neighbor model, or any fixed $d>6$ for spread-out models. We prove that there exist constants $\mathbf{C},\mathbf{C}'$ depending only on the dimension and the spread-out parameter such that for any $λ\in \mathbb{R}$ if the edge probability is $p_c(\mathbb{Z}^d)+\mathbf{C} λn^{-d/3} + o(n^{-d/3})$, then the joint distribution of the largest clusters normalized by $\mathbf{C}' n^{-2d/3}$ converges as $n\to \infty$ to the ordered lengths of excursions above past minimum of an inhomogeneous Brownian motion started at $0$ with drift $λ-t$ at time $t\in[0,\infty)$. This canonical limit was identified by Aldous in the context of critical Erdős--Rényi graphs.
