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Updated: Nov 27, 2025
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Definition and Time Evolution of Correlations in Classical Statistical Mechanics
1Formerly Department of Physics, Université de Mons-UMONS, Place du Parc 20, B-7000 Mons, Belgium.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
This study introduces a novel method to define and measure correlations in dense gases and liquids using information entropy. This approach unifies thermodynamic entropy and provides new approximations for molecular systems.
Area of Science:
- Statistical Mechanics
- Information Theory
- Thermodynamics
Background:
- Understanding particle interactions and correlations is crucial for dense gases and liquids.
- Existing methods for correlation analysis can be complex and system-specific.
Purpose of the Study:
- To develop a unified framework for defining and measuring correlations in stochastic systems.
- To establish a method applicable to both dilute and dense systems, and equilibrium/non-equilibrium states.
- To explore the relationship between information entropy and thermodynamic entropy.
Main Methods:
- Utilizing the N-variable distribution function that maximizes Shannon's information entropy.
- Defining N-order correlations based on the properties of this distribution function and its marginals.
- Applying the framework to derive grand-canonical expressions for uncertainty.
Main Results:
- A correlation-free definition for N-order correlations applicable to discrete/continuous variables and equilibrium/non-equilibrium states.
- Equivalence of the derived uncertainty to thermodynamic entropy for equilibrium systems.
- Derivation of the Kirkwood superposition approximation and generalized versions.
Conclusions:
- The information-theoretic approach provides a robust method for analyzing correlations in molecular systems.
- The study offers new insights into the origin of irreversibility in molecular systems, highlighting the role of three-body interactions.
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