UNIVERSALITY CHANGE IN STOCHASTIC CELLULAR AUTOMATION WITH APPLIED SITE EXCHANGE

Extended mean-field theory is used for studying the effect of nonlocal site exchange on the critical transition of the one-dimensional, stoc hastic cellular automaton of Rule 18 defined by Wolfram [Rev. Mod. Phy s. 55, 601 (1993)]. The analysis is carried out at different levels ta king n-point correlations explicitly into consideration. Extrapolation to the n --> infinity (exact) limit gives results, which agree well w ith simulation. By applying nonlocal site exchange mixing the universa lity of the transition changes and a continuous crossover of critical point and beta exponent is observed.