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Planetary dynamos: from equipartition to asymptopia

Published online by Cambridge University Press:  01 November 2008

Paul H. Roberts
Paul H. Roberts*
Affiliation:
IGPP University of California, Los Angeles, CA 90095, USA email: roberts@math.ucla.edu
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Abstract

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This review focuses on three topics relevant to naturally-occurring dynamos. The first considers how a common belief, that states of equipartition of magnetic and kinetic energy are preferred in nonrotating systems, is modified when Coriolis forces are influential, as in the Earth's core. The second reviews current difficulties faced by planetary and stellar dynamo theories, particularly in representing the sub-grid scales. The third discusses recent attempts to extract scaling laws from numerical integrations of the Boussinesq dynamo equations.

Keywords

Convection – turbulence – magnetic fields – instabilities

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