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Updated: Jun 14, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Spectrum of weak magnetohydrodynamic turbulence
Stanislav Boldyrev1, Jean Carlos Perez
1Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA.
Physical Review Letters
|April 7, 2010
Summary
Nonbalanced magnetohydrodynamic turbulence generates a condensate of residual energy, causing Alfvén wave spectra to deviate from scale invariance. This phenomenon is linked to the breakdown of mirror symmetry in wave dynamics.
Area of Science:
- Plasma physics
- Astrophysics
- Fluid dynamics
Background:
- Magnetohydrodynamic (MHD) turbulence is often cross-helical or nonbalanced, with unequal energies in oppositely directed Alfvén waves.
- This imbalance is prevalent in both natural phenomena and laboratory experiments.
Purpose of the Study:
- To investigate the spontaneous generation of energy condensates in nonbalanced MHD turbulence.
- To determine the impact of this condensate formation on the energy spectra of Alfvén waves.
- To explore the relationship between condensate generation and the breakdown of mirror symmetry.
Main Methods:
- High-resolution numerical simulations of MHD turbulence.
- Analysis of energy spectra of Alfvén waves at various wave numbers.
- Investigation of scaling laws in the limit of infinite Reynolds number.
Main Results:
- Nonbalanced MHD turbulence spontaneously generates a condensate of residual energy (E(v) - E(b)) at small field-parallel wave numbers.
- Alfvén wave energy spectra are not scale-invariant within a limited inertial interval due to condensate formation.
- Asymptotic restoration of universality and k(perpendicular)(-2) scaling for both spectra occur at large wave numbers in the infinite Reynolds number limit.
Conclusions:
- The generation of an energy condensate is a key feature of nonbalanced MHD turbulence.
- This condensate formation leads to a deviation from scale invariance in Alfvén wave spectra.
- The breakdown of mirror symmetry is intrinsically linked to the condensate generation process in MHD turbulence.
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