Related Experiment Video
Updated: Jan 16, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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Universal Scale-Free Decay of Tracer-Bath Correlations in d-Dimensional Interacting Particle Systems
Davide Venturelli1, Pierre Illien2, Aurélien Grabsch1
1Sorbonne Université, CNRS, Laboratoire de Physique Théorique de la Matière Condensée (LPTMC), 4 Place Jussieu, 75005 Paris, France.
Physical Review Letters
|October 5, 2025
Summary
This study quantifies tracer diffusion in particle systems by analyzing tracer position and surrounding particle density correlations. Unexpected universal power-law behaviors were discovered, dependent only on system dimensionality.
Area of Science:
- Statistical Mechanics
- Condensed Matter Physics
- Computational Physics
Background:
- Understanding tracer diffusion in interacting particle systems is key.
- Characterizing bath response properties requires analyzing particle correlations.
Purpose of the Study:
- To analytically quantify correlations between tracer position and surrounding bath particle density.
- To investigate these correlations in both hard-core and soft-core interacting particle models.
- To reveal universal features in tracer diffusion across different spatial dimensions.
Main Methods:
- Analytical derivation of spatial correlation profiles in the tracer's reference frame.
- Development of minimal, paradigmatic models for d-dimensional systems.
- Validation using particle-based numerical simulations across various regimes.
Main Results:
- Analytical expressions for spatial correlation profiles derived for hard-core and soft-core interactions.
- Discovery of universal large-distance behavior characterized by power-law tails.
- Exponents of power-law tails found to depend solely on spatial dimensionality.
Conclusions:
- The study provides a robust analytical framework for understanding tracer diffusion in interacting particle systems.
- Universal power-law behavior in correlation profiles highlights fundamental properties of diffusion in these systems.
- Numerical simulations confirm the validity and robustness of the analytical findings across different physical regimes.
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