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Brownian self-driven particles on the surface of a sphere
Leonardo Apaza1, Mario Sandoval2
1Faculty of Pure and Natural Sciences, Universidad Mayor de San Andres, La Paz, Bolivia.
We studied self-propelled particles on a sphere. We found how self-propulsion affects their diffusion and derived key equations for their movement dynamics.
Area of Science:
- Statistical Physics
- Soft Matter Physics
- Brownian Motion
Background:
- Brownian motion describes random particle movement.
- Self-propelled particles exhibit active movement.
- Spherical surfaces present unique dynamic constraints.
Purpose of the Study:
- To analyze the dynamics of overdamped Brownian self-propelled particles on a sphere.
- To elucidate the impact of self-propulsion on particle diffusion.
- To derive analytical expressions for particle displacement and probability distributions.
Main Methods:
- Calculating angular mean-square displacement (azimuthal and polar).
- Developing short- and long-time analytical expressions.
- Determining steady marginal angular probability density functions.
Main Results:
- Quantified the effect of self-propulsion on diffusion.
- Provided analytical expressions for angular mean-square displacement.
- Characterized the steady-state probability distributions of particle positions.
Conclusions:
- Self-propulsion significantly alters diffusion dynamics on spherical surfaces.
- Analytical models accurately describe particle behavior over different timescales.
- The study provides a framework for understanding active matter on curved substrates.
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