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arXiv · 0707.3012

Chaotic flows and cosmic dynamos in anisotropic pseudo-Riemannian four-dimensional spacetime

Abstract

It is shown that the existence of the cosmic kinematic fast dynamos in Bianchi type IX rotating cosmological models, faces severe difficulties, due to the fact that in these models rotation increases without bounds, which is strictly forbidden by CMB astronomical date which imposes strong bounds on its rotation with respect with its rapid expansion. The only way out of this difficulty is to assume that at least one of the expansion directions of this anisotropic universe decays as fast as the amplification rate of primordial magnetic fields. A solution is found where only one direction of the anisotropic universe expands while the other two remain constants. We compute an amplification of the seed magnetic field in the case where Bianchi IX degenerates into de Sitter metric, fields amplify from 10^{-6}G to 10^{-5}G in spiral galaxies for a cosmological constant of the order $|Λ|<10^{33}s^{-2}$ and considering that the age of universe of the order of 10^{10}yrs. Another example is given by the ABC chaotic flows in the pseudo-Riemannian spacetime representing the Kasner anisotropic nonsingular universe.

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Garcia de Andrade. 2007-07-20. Chaotic flows and cosmic dynamos in anisotropic pseudo-Riemannian four-dimensional spacetime. https://arxiv.org/abs/0707.3012

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