Oughton, SeanMatthaeus, William H.2026-08-022026-08-022020Oughton, S., & Matthaeus, W. H. (2020). Critical balance and the physics of magnetohydrodynamic turbulence. The Astrophysical Journal (ApJ), 897(1), 37-37. https://doi.org/10.3847/1538-4357/ab8f2a0004-637Xhttps://hdl.handle.net/10289/18499A discussion of the advantages and limitations of the concept of critical balance (CB), as employed in turbulence phenomenologies, is presented. The incompressible magnetohydrodynamic (MHD) case is a particular focus. The discussion emphasizes the status of the original Goldreich & Sridhar CB conjecture relative to related theoretical issues and models in an MHD description of plasma turbulence. Issues examined include variance and spectral anisotropy, influence of a mean magnetic field, local and nonlocal effects, and the potential for effects of external driving. Related models such as Reduced MHD provide a valuable context in the considerations. Some new results concerning spectral features and timescales are presented in the course of the discussion. Also mentioned briefly are some adaptations and variations of CB.en© 2020. The American Astronomical SocietyScience & TechnologyPhysical SciencesAstronomy & AstrophysicsAlfven wavesSpace plasmasInterplanetary turbulenceSpectral energy distributionSolar windMagnetohydrodynamicsMAGNETIC-FIELDSOLAR-WINDINTERSTELLAR TURBULENCEINERTIAL-RANGEALFVENIC FLUCTUATIONSENERGY-TRANSFERMHD TURBULENCEPOWER SPECTRAANISOTROPYWEAKJournal Article10.3847/1538-4357/ab8f2a1538-435746 Information and Computing Sciences4601 Applied Computing51 Physical Sciences5109 Space Sciences5107 Particle and High Energy Physics5101 Astronomical Sciences51 Physical Sciences5101 Astronomical sciences5107 Particle and high energy physics5109 Space sciences