Related Experiment Video
Updated: Jan 1, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Particle transport at arbitrary timescales with Poisson-distributed collisions.
M Baquero-Ruiz1, F Manke1, I Furno1
1École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland.
We modeled a persistent random walker experiencing random collisions. Transport properties change over time, with early behavior depending on initial conditions.
Area of Science:
- Physics
- Statistical Mechanics
- Stochastic Processes
Background:
- Random walkers are fundamental models in physics.
- Understanding transport properties is crucial in various scientific fields.
- Previous models often simplify collision dynamics.
Purpose of the Study:
- To model the time evolution of a persistent random walker's position and variance.
- To investigate the impact of Poisson-distributed collisions on transport properties.
- To analyze the influence of different velocity transition functions.
Main Methods:
- Developed a mathematical model for a random walker with velocity changes upon collision.
- Incorporated Poisson-distributed collisions at a constant rate.
- Studied three distinct velocity transition functions.
- Analyzed transport properties through the evolution of the variance.
Main Results:
- The model captures the time evolution of mean location and variance.
- Observed that transport properties can change their character over time.
- Early-time behavior of the walker is sensitive to initial conditions.
- Different velocity transition functions lead to varied transport characteristics.
Conclusions:
- The study provides insights into the complex dynamics of random walkers under intermittent velocity changes.
- Highlights the importance of considering time-dependent transport and initial conditions.
- The developed model offers a framework for studying similar stochastic systems.
Related Concept Videos
Poisson Probability Distribution
The...
Mean free path and Mean free time
Maxwell-Boltzmann Distribution: Problem Solving
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by
Collisions in Multiple Dimensions: Introduction
Poisson's And Laplace's Equation
Distribution of Molecular Speeds

