Abstract
We show analytically that the , , and Padé approximants of the mean cluster number for site and bond percolation on general -dimensional lattices are upper bounds on this quantity in any Euclidean dimension , where is the occupation probability. These results lead to certain lower bounds on the percolation threshold that become progressively tighter as increases and asymptotically exact as becomes large. These lower-bound estimates depend on the structure of the -dimensional lattice and whether site or bond percolation is being considered. We obtain explicit bounds on for both site and bond percolation on five different lattices: -dimensional generalizations of the simple-cubic, body-centered-cubic, and face-centered-cubic Bravais lattices as well as the -dimensional generalizations of the diamond and kagomé (or pyrochlore) non-Bravais lattices. These analytical estimates are used to assess available simulation results across dimensions (up through in some cases). It is noteworthy that the tightest lower bound provides reasonable estimates of in relatively low dimensions and becomes increasingly accurate as grows. We also derive high-dimensional asymptotic expansions for for the 10 percolation problems and compare them to the Bethe-lattice approximation. Finally, we remark on the radius of convergence of the series expansion of in powers of as the dimension grows.
- Received 1 February 2013
DOI:https://doi.org/10.1103/PhysRevE.87.032149
©2013 American Physical Society