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Updated: Jul 11, 2025
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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Trapped tracer in a non-equilibrium bath: dynamics and energetics
Koushik Goswami1, Ralf Metzler1,2
1Institute of Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany. goswamikoushik10@gmail.com.
Soft Matter
|November 10, 2023
Summary
We analyzed tracer dynamics in a non-equilibrium bath with active particles at different temperatures. Our findings provide a method to quantify non-equilibrium fluctuations using effective temperature and energy dissipation.
Area of Science:
- Statistical Mechanics
- Soft Matter Physics
- Biophysics
Background:
- Understanding non-equilibrium systems is crucial for biological processes.
- Active particles create unique environments with athermal fluctuations.
- Tracer dynamics can reveal properties of complex media.
Purpose of the Study:
- To investigate the dynamics of a tracer particle in a non-equilibrium bath.
- To develop analytical methods for characterizing effective motion.
- To quantify non-equilibrium fluctuations and energy dissipation.
Main Methods:
- Analytical solution of the probability density function for tracer motion.
- Numerical simulations to support analytical findings.
- Analysis of response function and power spectrum.
Main Results:
- Exact solution for the tracer's effective motion probability density function.
- Measurement of non-equilibrium fluctuations via effective temperature.
- Quantification of energy dissipation and the impact of particle activity.
Conclusions:
- The study provides a framework for understanding tracer dynamics in active baths.
- Experimental observables can effectively characterize non-equilibrium fluctuations.
- Relevant for cytoskeletal networks and intracellular environments.
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