Perfect magnetohydrodynamics as a field theory

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.74.083009· OSTI ID:20871370

Bekenstein, Jacob D; Betschart, Gerold ^[1]

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1. Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904 (Israel)

We propose the generally covariant action for the theory of a self-coupled complex scalar field and electromagnetism which by virtue of constraints is equivalent, in the regime of long wavelengths, to perfect magnetohydrodynamics (MHD). We recover from it the Euler equation with Lorentz force, and the thermodynamic relations for a prefect fluid. The equation of state of the latter is related to the scalar field's self potential. We introduce 1+3 notation to elucidate the relation between MHD and field variables. In our approach the requirement that the scalar field be single valued leads to the quantization of a certain circulation in steps of ({Dirac_h}/2{pi}); this feature leads, in the classical limit, to the conservation of that circulation. The circulation is identical to that in Oron's generalization of Kelvin's circulation theorem to perfect MHD; we here characterize the new conserved helicity associated with it. We also demonstrate the existence for MHD of two Bernoulli-like theorems for each spacetime symmetry of the flow and geometry; one of these is pertinent to suitably defined potential flow. We exhibit the conserved quantities explicitly in the case that two symmetries are simultaneously present, and give examples. Also in this case we exhibit a new conserved MHD circulation distinct from Oron's, and provide an example.

• OSTI ID: 20871370
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 8 Vol. 74; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ELECTROMAGNETISM
EQUATIONS OF STATE
GEOMETRY
HELICITY
LORENTZ FORCE
MAGNETOHYDRODYNAMICS
POTENTIAL FLOW
POTENTIALS
QUANTIZATION
QUANTUM FIELD THEORY
SCALAR FIELDS
SPACE-TIME
SYMMETRY
WAVELENGTHS