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Partition Function and Configurational Entropy in Non-Equilibrium States: A New Theoretical Model
Akira Takada1,2, Reinhard Conradt3, Pascal Richet4
1Innovative Technology Research Center, Asahi Glass Co. Ltd., Yokohama 221-8755, Japan.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
This study introduces a novel thermodynamic model using pseudo-temperatures to describe non-equilibrium states. This approach allows for a unified description of both equilibrium and non-equilibrium systems, revealing cooling and relaxation effects.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Computational Physics
Background:
- Traditional thermodynamics primarily focuses on equilibrium states.
- Describing non-equilibrium thermodynamic states remains a significant challenge.
- Partition functions are fundamental to deriving thermodynamic variables.
Purpose of the Study:
- To develop a new model for non-equilibrium thermodynamic states.
- To define partition functions applicable to non-equilibrium conditions.
- To investigate cooling and relaxation phenomena in non-equilibrium systems.
Main Methods:
- Introduction of pseudo-temperature distributions, distinct from kinetic temperatures.
- Formulation of an extended canonical partition function based on pseudo-temperatures.
- Computational experiments on simple non-interacting systems.
Main Results:
- A unified framework for describing both equilibrium and non-equilibrium thermodynamic states.
- Derivation of internal energy and entropy from the new pseudo-temperature definition.
- Observation of cooling and two distinct relaxational effects over time.
Conclusions:
- The pseudo-temperature model provides a robust method for analyzing non-equilibrium thermodynamics.
- The model successfully describes cooling and relaxation dynamics.
- This framework offers new avenues for studying complex thermodynamic systems.
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