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Ensembles, turbulence and fluctuation theorem
1INFN Roma1, and Accademia dei Lincei, Roma, Italy. giovanni.gallavotti@roma1.infn.it.
The European Physical Journal. E, Soft Matter
|June 12, 2020
Summary
This study explores fluctuation relations in irreversible systems, using 2D Navier-Stokes flow as an example. It demonstrates how universal fluctuation properties can be predicted even in irreversible processes.
Area of Science:
- Statistical Mechanics
- Fluid Dynamics
- Non-equilibrium Thermodynamics
Background:
- The fluctuation theorem is typically linked to reversible systems.
- Its consequence, the fluctuation relation, is often deemed inapplicable to irreversible processes.
Purpose of the Study:
- To investigate the applicability of fluctuation relations in irreversible systems.
- To demonstrate universal properties of fluctuations in irreversible evolution using a specific example.
- To establish a theoretical framework for predicting fluctuation behavior in non-equilibrium systems.
Main Methods:
- Consideration of the 2D Navier-Stokes incompressible flow as a paradigmatic example of irreversible evolution.
- Formulation of a theoretical framework for analyzing fluctuations.
- Numerical simulations to illustrate predicted results.
Main Results:
- The study shows that universal properties of fluctuations can be predicted in systems undergoing irreversible evolution.
- Demonstrates the potential applicability of fluctuation relations beyond reversible systems.
- Provides simulation data supporting the theoretical predictions.
Conclusions:
- Fluctuation relations can offer insights into irreversible processes.
- The 2D Navier-Stokes flow serves as a valuable model for studying non-equilibrium fluctuations.
- Further research and simulations are needed to explore open questions and validate the framework.
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