Synchronous versus asynchronous updating in the “game of Life”

Abstract

The rules for the ``game of Life'' are modified to allow for only a random fraction of sites to be updated in each time step. Under variation of this fraction from the parallel updating limit down to the Poisson limit, a critical phase transition is observed that explains why the game of Life appears to obey self-organized criticality. The critical exponents are calculated and the static exponents appear to belong to the directed percolation universality class in 2+1 dimensions. The dynamic exponents, however, are nonuniversal, as seen in other systems with multiple absorbing states.