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Aggregation-fragmentation-diffusion model for trail dynamics.
Kyle Kawagoe1,2, Greg Huber1, Marc Pradas1,3
1Kavli Institute for Theoretical Physics, University of California Santa Barbara, California 93106, USA.
This study explores random trails with aggregation, fragmentation, and diffusion. We found the trail weight distribution follows a power law, with an exponent that changes based on model parameters, affecting small trail abundance.
Area of Science:
- Statistical physics
- Stochastic processes
- Complex systems
Background:
- Understanding the statistical properties of systems with aggregation, fragmentation, and diffusion is crucial.
- Trails formed by random processes exhibit complex behaviors.
Purpose of the Study:
- To investigate the statistical properties of trails in a 1D stochastic process.
- To determine the limiting distribution of trail weights in the long-time limit.
- To analytically derive the exponent of the power-law tail in the trail weight distribution.
Main Methods:
- Modeling a 1D stochastic process with aggregation, fragmentation, and diffusive movement of trails.
- Analyzing the system's steady-state behavior.
- Deriving the exponent of the power-law tail (P(w) ~ w^-γ) for small trail weights.
Main Results:
- The trail weight distribution exhibits a power-law tail P(w) ~ w^-γ for small weights.
- The exponent γ is obtained analytically and varies continuously with fragmentation rate and fragment size.
- The exponent γ can be positive or negative, leading to either abundant or rare small-weight trails.
Conclusions:
- The model provides insights into the statistical mechanics of systems with competing aggregation and fragmentation processes.
- The continuous variation of the exponent γ offers a tunable mechanism for controlling the abundance of small-weight entities.
- This research contributes to understanding complex systems with dynamic fragmentation and aggregation behaviors.
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