Scaling properties of the cluster distribution of a critical nonequilibrium model

A geometric approach to critical fluctuations of a nonequilibrium model is reported. The two-dimensional majority vote model was investigated by Monte Carlo simulations on square lattices of various sizes and a detailed scaling analysis of cluster statistical and geometric properties was performed. The cluster distribution exponents and fractal dimension were found to be the same as those of the (two-dimensional) Ising model. This result, which cannot be derived purely from the known bulk critical behaviour, widens our knowledge about the range of validity of the Ising universality class for nonequilibrium systems.