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Mean field electrodynamics: triumphs and tribulations

Part of: 50 years of Mean Field Electrodynamics

Published online by Cambridge University Press:  13 August 2018

David W. Hughes
David W. Hughes*
Affiliation:
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK
*
†Email address for correspondence: d.w.hughes@leeds.ac.uk
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Abstract

The theory of mean field electrodynamics, now celebrating its fiftieth birthday, has had a profound influence on our modelling of cosmical dynamos, greatly enhancing our understanding of how such dynamos may operate. Here I discuss some of its undoubted triumphs, but also some of the problems that can arise in a mean field approach to dynamos in fluids (or plasmas) that are both highly turbulent and also extremely good electrical conductors, as found in all astrophysical settings.

Keywords

astrophysical plasmas
Type
Research Article
Information
Journal of Plasma Physics , Volume 84 , Issue 4 , August 2018 , 735840407
Copyright
© Cambridge University Press 2018 

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