STRESSED BACKBONE AND ELASTICITY OF RANDOM CENTRAL-FORCE SYSTEMS

We use a new algorithm to find the stress-carrying backbone of ''gener ic'' site-diluted triangular lattices of up to 10(6) sites. Generic la ttices can be made by randomly displacing the sites of a regular latti ce. The percolation threshold is p(c) = 0.6975 +/- 0.0003, the correla tion length exponent nu = 1.16 +/- 0.03, and the fractal dimension of the backbone D-b = 1.78 +/- 0.02. The number of ''critical bonds'' (if you remove them rigidity is lost) on the backbone scales as L(x), wit h x = 0.85 +/- 0.05. The Young's modulus is also calculated.