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Slow dynamos and decay of monopole magnetic fields in the early Universe

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 نشر من قبل L. C. Garcia de Andrade
 تاريخ النشر 2009
  مجال البحث فيزياء
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 تأليف Garcia de Andrade




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Previously Liao and Shuryak [textbf{Phys. Rev C (2008)}] have investigated electrical flux tubes in monopole plasmas, where magnetic fields are non-solenoidal in quark-QCD plasmas. In this paper slow dynamos in diffusive plasma [{textbf{Phys. Plasmas textbf{15} (2008)}}] filaments (thin tubes) are obtained in the case of monopole plasmas. In the absence of diffusion the magnetic field decays in the Early Universe. The torsion is highly chaotic in dissipative large scale dynamos in the presence of magnetic monopoles. The magnetic field is given by the Heaviside step function in order to represent the non-uniform stretching of the dynamo filament. These results are obtained outside the junction condition. Stringent limits to the monopole flux were found by Lewis et al [textbf{Phys Rev D (2000)}] by using the dispute between the dynamo action and monopole flux. Since magnetic monopoles flow dispute the dynamo action, it seems reasonable that their presence leads to a slow dynamo action in the best hypothesis or a decay of the magnetic field. Hindmarsh et al have computed the magnetic energy decay in the early universe as ${E}_{M}approx{t^{-0.5}}$, while in our slow dynamo case linearization of the growth rate leads to a variation od magnetic energy of ${delta}{E}_{M}approx{t}$, due to the presence of magnetic monopoles. Da Rios equations of vortex filaments are used to place constraints on the geometry of monopole plasma filaments.

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