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Effect of noise on defect chaos in a reaction-diffusion model
1Department of Physics and State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871, People's Republic of China.
Chaos (Woodbury, N.Y.)
|July 23, 2005
Summary
Noise significantly impacts defect chaos in spiral waves, altering defect creation and annihilation rates. This study reveals noise-induced changes in defect distributions, deviating from previous models.
Area of Science:
- Nonlinear dynamics
- Complex systems
Background:
- Spiral waves are common in various complex systems.
- Defect chaos arises from spiral wave instabilities.
- Noise can influence system dynamics.
Purpose of the Study:
- Investigate the effect of noise on defect chaos in spiral waves.
- Analyze how noise impacts defect creation and annihilation rates.
- Examine the probability distribution of defects under noisy conditions.
Main Methods:
- Numerical simulations using a modified Fitzhugh-Nagumo model.
- Analysis of defect creation and annihilation rates.
- Comparison of defect probability distributions with theoretical models.
Main Results:
- Noise drastically enhances defect creation and annihilation rates.
- Noise-induced defect distributions deviate from the squared-Poisson distribution.
- Flattened distributions under noise can fit squared-Poisson or modified-Poisson models.
Conclusions:
- Noise plays a crucial role in defect chaos dynamics.
- The modified Fitzhugh-Nagumo model with noise exhibits unique defect behavior.
- Further research is needed to fully understand noise-induced defect dynamics.
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