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Published on: December 4, 2017
Entropy production and the geometry of dissipative evolution equations
Celia Reina1, Johannes Zimmer2
1Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
This study introduces a maximum entropy production principle that links system constraints to the geometry of dissipative evolution equations. This framework naturally incorporates Wasserstein geometry and extends Onsager relations to non-flux variables.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Systems
Background:
- Dissipative evolution equations often use gradient flow structures (ż=K(z)DS(z)) where S is a functional and K defines geometry.
- The operator K and its associated geometry (e.g., Wasserstein) are not always directly derived from physical principles.
Purpose of the Study:
- To present a variational principle based on maximum entropy production.
- To establish a direct relationship between the operator K and system constraints.
- To extend classical Onsager relations to non-flux variables in open systems.
Main Methods:
- Formulating a variational statement based on maximum entropy production.
- Demonstrating the emergence of Wasserstein metric from mass/energy conservation.
- Connecting the metric structure K to Freidlin-Wentzell theory.
Main Results:
- The Wasserstein metric arises naturally from conservation laws and depends on the Onsager resistivity tensor.
- The variational principle extends Onsager flux-force relationships to non-conserved quantities.
- The metric structure K is linked to stochastic perturbation theory of gradient flows.
Conclusions:
- The proposed variational principle provides a unified framework for understanding dissipative systems.
- It offers insights into the geometric structure of evolution equations and their relation to physical constraints.
- The principle encompasses an infinite-dimensional fluctuation-dissipation statement.
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