Oughton, SeanMatthaeus, William H.Dmitruk, Pablo2017-05-232017-04-102017-05-232017-04-10Oughton, S., Matthaeus, W. H., & Dmitruk, P. (2017). Reduced MHD in Astrophysical Applications: Two-dimensional or Three-dimensional? The Astrophysical Journal, 839(1). https://doi.org/10.3847/1538-4357/aa67e20004-637Xhttps://hdl.handle.net/10289/11075Originally proposed as an efficient approach to computation of nonlinear dynamics in tokamak fusion research devices, reduced magnetohydrodynamics (RMHD) has subsequently found application in studies of coronal heating, flux tube dynamics, charged particle transport, and, in general, as an approximation to describe plasma turbulence in space physics and astrophysics. Given the diverse set of derivations available in the literature, there has emerged some level of discussion and a lack of consensus regarding the completeness of RMHD as a turbulence model, and its applicability in contexts such as the solar wind. Some of the key issues in this discussion are examined here, emphasizing that RMHD is properly neither 2D nor fully 3D, being rather an incomplete representation that enforces at least one family of extraneous conservation laws.application/pdfenThis is an author’s accepted version of an article published in the journal: The Astrophysical Journal. © 2017 The American Astronomical Society.Science & TechnologyPhysical SciencesAstronomy & Astrophysicsmagnetohydrodynamics (MHD)methods: numericalplasmasSun: coronaSun: magnetic fieldsturbulenceCOMPRESSIBLE MAGNETOHYDRODYNAMIC TURBULENCERESOLUTION HYBRID SIMULATIONSMAGNETIC-FIELD CORRELATIONALFVEN-WAVE TURBULENCESOLAR-WINDINCOMPRESSIBLE FLUIDSVARIANCE ANISOTROPYSTRAUSS EQUATIONSINERTIAL RANGECORONAJournal Article10.3847/1538-4357/aa67e21538-4357