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Generalized contact process with two symmetric absorbing states in two dimensions
1Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA.
Summary
We studied the two-dimensional generalized contact process using simulations. An infinitesimal activation rate drives a phase transition, showing two distinct nonequilibrium transitions, one matching the generalized voter model.
Area of Science:
- Statistical Physics
- Complex Systems
Background:
- The generalized contact process is a model for population dynamics.
- Understanding nonequilibrium phase transitions is crucial in complex systems.
Purpose of the Study:
- To investigate the two-dimensional generalized contact process with two absorbing states.
- To characterize the system's phase transitions and universality classes.
Main Methods:
- Large-scale Monte Carlo simulations were employed.
- The phase diagram was explored, focusing on domain-boundary activation rates.
Main Results:
- Two distinct nonequilibrium phase transitions were identified.
- The generic transition aligns with the generalized voter universality class.
- A transition at zero domain-boundary activation rate was found to be non-critical.
Conclusions:
- The study reveals complex phase transition behavior in the generalized contact process.
- Symmetry-breaking and absorbing transitions coincide in the generic case.
- The system exhibits rich critical phenomena dependent on activation rates.
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