Numerical study of persistence in models with absorbing states - art. no. 031104

Extensive Monte Carlo simulations are performed in order to evaluate both t he local(theta (l)) and global(theta (g)) persistence exponents in the Ziff -Gulari-Barshad (ZGB) [Phys. Rev. Lett. 56, 2553 (1986)] irreversible react ion model. At the second-order irreversible phase transition (IPT) we find that both the local and the global persistence exhibit power-law behavior w ith a crossover between two different time regimes. On the other hand, at t he ZGB first-order IPT, active sites are short lived and the persistence de cays more abruptly; it is not clear whether it shows power-law behavior or not. In order to analyze universality issues, we have also studied another model with absorbing states, the contact process, and evaluated the local p ersistence exponent in dimensions from 1 to 4. A striking apparent superuni versality is reported: the local persistence exponent seems to coincide in both one- and two-dimensional systems. Some other aspects of persistence in systems with absorbing states are also analyzed.