Hyperdiffusion in nonlinear large- and small-scale turbulent dynamos.

@article{Subramanian2003HyperdiffusionIN,
  title={Hyperdiffusion in nonlinear large- and small-scale turbulent dynamos.},
  author={Kandaswamy Subramanian},
  journal={Physical review letters},
  year={2003},
  volume={90 24},
  pages={
          245003
        }
}
  • K. Subramanian
  • Published 2 March 2003
  • Physics, Medicine
  • Physical review letters
The generation of large-scale magnetic fields is generically accompanied by the more rapid growth of small-scale fields. The growing Lorentz force due to these fields backreacts on the turbulence to saturate the mean-field and small-scale dynamos. For the mean-field dynamo, in a quasilinear treatment of this saturation, it is generally thought that, while the alpha effect gets renormalized and suppressed by nonlinear effects, the turbulent diffusion is left unchanged. We show here that this is… Expand

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References

SHOWING 1-10 OF 22 REFERENCES
The Almighty Chance
This book is about the importance of random phenomena occurring in nature. Cases are selected in which randomness is most important or crucial, such as Brownian motion, certain reactions in PhysicalExpand
Magnetic Field Generation in Electrically Conducting Fluids
H K Moffatt 1983 Cambridge: Cambridge University Press x + 343 pp price £12.50 (paperback) ISBN 0 521 27583 0 Professor Moffatt has written a careful account of a subject of fundamental importanceExpand
"J."
however (for it was the literal soul of the life of the Redeemer, John xv. io), is the peculiar token of fellowship with the Redeemer. That love to God (what is meant here is not God’s love to men)Expand
Astrophys
  • J., 550, 824
  • 2001
astro-ph/9708216; MNRAS
  • 294, 718 (1998); K. Subramanian, Phys. Rev. Lett., 83, 2957 (1999); A. Brandenburg and K. Subramanian, Astron. & Astrophys., 361, L33
  • 2000
Sov
  • Phys. JETP, 26, 1031 (1968); Ya. B. Zeldovich, A. A. Ruzmaikin and D. D. Sokoloff, The almighty chance, World Scientific, Singapore (1990); S. Vainshtein and L. L. Kichatinov, J. Fluid. Mech., 168, 73 (1986); R. M. Kulsrud, and S.W. Anderson, Astrophys. J., 396, 606 (1992); A. Schekochihin, S. Cowle
  • 2001
Phys
  • Rev. Lett., 72, 1651 (1994); K. Avinash, Phys. Fluids B, 3, 2150
  • 1991
Magnetic fields in Astrophysics, Gordon and Breach, New York
  • Cosmic magnetic fields,
  • 1978
Astron
  • & Astrophys., 361, L5 (2000); 387, 453 (2002); E. Blackman & A. Brandenburg, Astrophys. J., 579, 359 (2002); K. Subramanian, Bull. Astr. Soc. India, 30, 715
  • 2002
Phys
  • Lett. A., 259, 232 (1999); A. Schekochihin, S. Cowley, G. W. Hammett, J. Maron, J. C. McWilliams, New Jour. of Phys., 4, 84
  • 2002
...
1
2
3
...