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arXiv · 0905.2001

Cosmic dynamo analogue and decay of magnetic fields in 3D Ricci flows

Garcia de Andrade
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Abstract

Magnetic curvature effects, investigated by Barrow and Tsagas (BT) [Phys Rev D \textbf{77},(2008)],as a mechanism for magnetic field decay in open Friedmann universes ($Λ<0$), are applied to dynamo geometric Ricci flows in 3D curved substrate in laboratory. By simple derivation, a covariant three-dimensional magnetic self-induced equation, presence of these curvature effects, indicates that de Sitter cosmological constant ($Λ\ge{0}$), leads to enhancement in the fast kinematic dynamo action which adds to stretching of plasma flows. From the magnetic growth rate, the strong shear case, anti-de Sitter case ($Λ<0$) BT magnetic decaying fields are possible while for weak shear, fast dynamos are possible. The self-induced equation in Ricci flows is similar to the equation derived by BT in $(3+1)$-spacetime continuum. Lyapunov-de Sitter metric is obtained from Ricci flow eigenvalue problem. In de Sitter analogue there is a decay rate of $γ\approx{-Λ}\approx{-10^{-35}s^{-2}}$ from corresponding cosmological constant $Λ$, showing that, even in the dynamo case, magnetic field growth is slower than de Sitter inflation, which strongly supports to BT result.

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Garcia de Andrade. 2009-05-13. Cosmic dynamo analogue and decay of magnetic fields in 3D Ricci flows. https://arxiv.org/abs/0905.2001

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