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The thermodynamic processes can be classified into reversible and irreversible processes. The processes that can be restored to their initial state are called reversible processes. It is only possible if the process is in quasi-static equilibrium, i.e., it takes place in infinitesimally small steps, and the system remains at equilibrium However, these are ideal processes and do not occur naturally. An ideal system undergoing a reversible process is always in thermodynamic equilibrium within...

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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

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Far-from-equilibrium processes without net thermal exchange via energy sorting.

Jose M G Vilar¹, J Miguel Rubi

¹Biophysics Unit (CSIC-UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, 48080 Bilbao, Spain. j.vilar@ikerbasque.org

The Journal of Chemical Physics

|February 25, 2012

Summary

Scientists discovered "ghost equilibrium," a new far-from-equilibrium process that controls microscale systems without disturbing thermal properties. This method enables precise energy manipulation in nanoscale devices by suppressing environmental heat exchange.

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Area of Science:

Microscale physics
Statistical mechanics
Non-equilibrium thermodynamics

Background:

Many microscale processes require far-from-equilibrium conditions.
Energy inputs for these conditions often disrupt thermal properties and system control.
Existing methods lack precise control over thermal exchange.

Purpose of the Study:

To introduce a novel class of far-from-equilibrium processes.
To demonstrate a method for suppressing net thermal exchange with the environment.
To enable controlled energy manipulation at the microscale.

Main Methods:

Statistical cancellation of nonequilibrated degrees of freedom.
Microscale energy sorting process.
Analysis of Maxwell-Boltzmann velocity distribution maintenance.
Application to rotational dipoles and trapped particle gases.

Main Results:

A phenomenon termed "ghost equilibrium" was identified.
Ghost equilibrium suppresses net thermal exchange while maintaining equilibrium velocity distribution.
Autonomous generation of superheated and subcooled degrees of freedom.
Demonstrated control over energy in microscale systems.

Conclusions:

Ghost equilibrium offers a new paradigm for far-from-equilibrium processes.
This phenomenon allows for precise control of microscale systems.
Potential applications in mesoscopic bioreactors, nanoscopic rotors, and nanoscale mass conveyors.