Related Experiment Video
Updated: Jun 12, 2026

11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Generalized Green-Kubo relation and integral fluctuation theorem for driven dissipative systems without microscopic
Song-Ho Chong1, Michio Otsuki, Hisao Hayakawa
1Institute for Molecular Science, Okazaki 444-8585, Japan.
Summary
We developed new statistical mechanics theories for driven dissipative systems, extending the Green-Kubo relation and fluctuation theorem. This work addresses systems far from equilibrium, like sheared granular materials.
Area of Science:
- Statistical mechanics
- Non-equilibrium thermodynamics
- Complex systems
Background:
- Traditional statistical mechanics often assumes equilibrium or near-equilibrium conditions.
- Driven dissipative systems, characterized by broken time-reversal symmetry, pose challenges for existing theories.
- Understanding non-equilibrium steady states is crucial for many physical phenomena.
Purpose of the Study:
- To derive a generalized Green-Kubo relation applicable to driven dissipative systems.
- To formulate an integral form of the fluctuation theorem for systems with broken detailed balance.
- To establish a framework for statistical mechanical theories of non-equilibrium steady states.
Main Methods:
- Derivation of generalized Green-Kubo relations.
- Formulation of an integral fluctuation theorem.
- Application to specific models: uniformly sheared granular systems and driven inelastic Lorentz gas.
Main Results:
- Successfully derived generalized Green-Kubo and fluctuation relations for driven dissipative systems.
- Demonstrated the applicability of these relations to granular materials and Lorentz gas models.
- Provided a pathway for constructing statistical mechanical theories for systems lacking equilibrium.
Conclusions:
- The derived relations offer powerful tools for analyzing non-equilibrium steady states.
- These findings advance the statistical mechanical understanding of systems far from equilibrium.
- The theoretical framework is applicable to a range of complex, driven systems.
Related Concept Videos
The Entropy as a State Function
Consider an arbitrary process that moves between two specific states (A and B) in a cyclic manner. This process is reversible and broken down into smaller parts that each follow a Carnot cycle. A Carnot cycle has two isothermal (constant temperature) processes. During these processes, the ratio of the amount of heat transferred to their respective temperature remains constant. The other two processes in the Carnot cycle are also reversible but adiabatic, which means they occur without any heat...
Reynolds Transport Theorem
The Reynolds transport theorem provides a framework to relate the time rate of change of an extensive property within a system to that in a control volume, which is crucial for analyzing fluid dynamics. Extensive properties, such as mass, velocity, acceleration, temperature, and momentum, can be expressed in terms of the mass of a fluid portion. These properties are called extensive because they depend on the system's size, while intensive properties are their corresponding values per unit mass.
Extended Versions of Green’s Theorem
Green’s Theorem connects the circulation of a vector field around a closed curve with the behavior of the field across the region enclosed by that curve. It provides a way to replace a line integral around a boundary with a double integral over the interior region, making it especially useful in plane geometry, fluid flow, and vector calculus.Although Green’s Theorem is often introduced using simple regions without gaps, it can also be applied to regions made from several simple parts. This...
Entropy
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
Entropy
The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
Entropy Change in Reversible Processes
In the Carnot engine, which achieves the maximum efficiency between two reservoirs of fixed temperatures, the total change in entropy is zero. The observation can be generalized by considering any reversible cyclic process consisting of many Carnot cycles. Thus, it can be stated that the total entropy change of any ideal reversible cycle is zero.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
