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Updated: Jul 28, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Metastability and weak mixing in classical long-range many-rotator systems
Benedito J C Cabral1, Constantino Tsallis
1Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa, Edifício C8, Portugal.
Summary
This study explores a classical Hamiltonian system
Area of Science:
- Statistical Mechanics
- Complex Systems Dynamics
Background:
- The system exhibits a second-order phase transition.
- Behavior depends on the parameter alpha/d, related to nonextensivity.
Purpose of the Study:
- Investigate the dynamics of a classical Hamiltonian system.
- Analyze the system's behavior in the nonextensive regime (alpha/d <= 1).
Main Methods:
- Molecular dynamics simulation.
- Analysis of the maximal Lyapunov exponent.
Main Results:
- For u < u(c), the system exhibits a metastable state before reaching the stable state.
- The maximal Lyapunov exponent in the metastable state scales with N^(-kappa_metastable).
- kappa_metastable is numerically one-third of its value for u > u(c) and decreases with increasing alpha/d.
Conclusions:
- A connection exists between dynamics above and below the critical point.
- Results support a nonextensive universality scenario.
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