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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Einstein relation and hydrodynamics of nonequilibrium mass transport processes
Arghya Das1, Anupam Kundu2, Punyabrata Pradhan1
1Department of Theoretical Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106, India.
Physical Review. E
|July 16, 2017
Summary
This study reveals that transport coefficients in mass transport systems obey an Einstein relation, even far from equilibrium. This finding holds true for systems with chipping, diffusion, and coalescence dynamics.
Area of Science:
- Statistical Mechanics
- Non-equilibrium Physics
- Transport Phenomena
Background:
- Conserved-mass transport processes on a ring are fundamental models in statistical mechanics.
- These systems often reach a non-equilibrium steady state with complex correlations.
- Analytical solutions for steady-state measures are frequently unknown.
Purpose of the Study:
- To derive the hydrodynamics of paradigmatic conserved-mass transport processes.
- To analytically calculate transport coefficients like bulk-diffusion and conductivity.
- To investigate the validity of the Einstein relation in non-equilibrium systems.
Main Methods:
- Derivation of hydrodynamics for chipping, diffusion, and coalescence dynamics.
- Analytical calculation of bulk-diffusion coefficient and conductivity.
- Application of macroscopic fluctuation theory.
Main Results:
- Transport coefficients were analytically calculated for the first time.
- An equilibrium-like Einstein relation was found to hold, despite violation of detailed balance.
- Large deviation probabilities for density matched previous findings.
Conclusions:
- The Einstein relation is robust and applicable even in far-from-equilibrium systems.
- Hydrodynamic descriptions provide accurate predictions for transport phenomena.
- This work offers a deeper understanding of non-equilibrium statistical mechanics.
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