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Nonexistence of equilibrium states at absolute negative temperatures
1Instituto de Física, Universidad Nacional Autónoma de México and Apartado Postal 20-364, 01000 México D.F. Mexico.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 17, 2013
Summary
Systems with absolute negative temperatures are shown to be unstable. This instability means that such states cannot exist in thermodynamic equilibrium, rendering the Ramsey identification of negative temperatures untenable.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Physical Systems
Background:
- Absolute negative temperatures are a theoretical concept in thermodynamics.
- The stability of such states under perturbations is crucial for their physical relevance.
Purpose of the Study:
- To investigate the stability of macroscopic systems with purported absolute negative temperatures.
- To determine the physical tenability of Ramsey's theoretical reformulation for negative temperatures.
Main Methods:
- Analysis of system stability under small, arbitrary perturbations.
- Utilizing the principle that entropy is maximized at equilibrium.
Main Results:
- States with absolute negative temperatures are proven to be unstable.
- The assumption of thermodynamic equilibrium for negative temperature states is shown to be invalid.
Conclusions:
- The physical occurrence of states with absolute negative temperatures is impossible.
- Reversible processes are not possible for these purported states.
- Ramsey's identification of absolute negative temperatures is consequently untenable.
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