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Published on: August 5, 2016
Simple sandpile model of active-absorbing state transitions
1Institut für Theoretische Physik, Universität zu Köln, 50937 Köln, Germany.
Summary
This study explores a sandpile model, revealing distinct behaviors in active and absorbing phases. The active phase exhibits simple product measure, while the absorbing phase shows complex correlations and slow relaxation dynamics.
Area of Science:
- Statistical Physics
- Complex Systems
Background:
- Active-absorbing phase transitions are fundamental in statistical physics.
- Sandpile models offer a framework to study self-organized criticality and emergent phenomena.
Purpose of the Study:
- To investigate a simple sandpile model with a threshold-based particle hopping mechanism.
- To characterize the distinct phases and critical behavior of this model.
Main Methods:
- Numerical simulations were employed to analyze the absorbing phase.
- Theoretical analysis was used to describe the active phase and relaxation dynamics.
Main Results:
- The active phase was found to possess a product measure.
- Nontrivial correlations were observed numerically in the absorbing phase.
- The system's relaxation to the absorbing state is slower than exponential.
Conclusions:
- The critical behavior of this sandpile model differs from established universality classes.
- The model presents a unique case study for active-absorbing phase transitions.
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