A unified scaling for the optimal path length in disordered lattices

Abstract

In recent decades, much attention has been focused on the topic of optimal paths in weighted networks due to its broad scientific interest and technological applications. In this work we revisit the problem of the optimal path between two points and focus on the role of the geometry (size and shape) of the embedding lattice, which has received very little attention. This role becomes crucial, for example, in the strong disorder limit, where the mean length of the optimal path for a fixed end-to-end distance diverges as the lattice size increases. We propose a unified scaling ansatz for the mean length of the optimal path in $D-$dimensional disordered lattices. The ansatz is supported by a comprehensive numerical study of the problem on $2D$ lattices, yet we also present results in $D=3$. We show that it unifies well-known results in the strong and weak disorder regimes, including the crossover behavior, but it also reveals novel scaling scenarios not yet addressed. Moreover, it provides relevant insights into the origin of the universal exponents that characterize the scaling of the optimal path in the strong disorder limit.