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Published on: March 30, 2017
Nonthermal fixed points: effective weak coupling for strongly correlated systems far from equilibrium
Jürgen Berges1, Alexander Rothkopf, Jonas Schmidt
1Institute for Nuclear Physics, Darmstadt University of Technology, Schlossgartenstr. 9, 64285 Darmstadt, Germany.
Physical Review Letters
|September 4, 2008
Summary
Strongly correlated systems far from equilibrium can develop weak coupling, preventing rapid thermalization. This occurs when classical-statistical fluctuations dominate quantum fluctuations in relativistic quantum field theories.
Area of Science:
- Quantum Field Theory
- Non-equilibrium Physics
- Cosmology
Background:
- Strongly correlated systems far from equilibrium present challenges for theoretical description.
- Understanding thermalization dynamics is crucial in various physics domains.
Purpose of the Study:
- Investigate scaling solutions in isolated systems under non-equilibrium conditions.
- Determine the role of fluctuations in preventing fast thermalization.
Main Methods:
- Utilizing relativistic quantum field theories.
- Analyzing initial conditions leading to non-equilibrium instabilities like parametric resonance and spinodal decomposition.
- Examining the interplay between classical-statistical and quantum fluctuations.
Main Results:
- Demonstrated the emergence of scaling solutions with dynamically generated weak coupling.
- Identified non-thermal fixed points that hinder rapid thermalization.
- Showed that classical-statistical fluctuations can dominate over quantum fluctuations.
Conclusions:
- Non-thermal fixed points and dominant classical-statistical fluctuations can prevent fast thermalization in strongly correlated systems.
- These findings have implications for early Universe cosmology and heavy-ion collisions.
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