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arXiv · 1401.2587

Galactic dynamo seeds from non-superconducting spin-polarised strings

L. C. Garcia de Andrade
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Abstract

Earlier Enqvist and Olesen have shown that formation of ferromagnetic planar walls in vacuum at GUT scales in comoving plasmas may generate a large scale magnetic field of $B_{now}\simeq{10^{-14}G}$. In this paper we show that starting from classical Einstein-Cartan-Maxwell strong gravity, a spin-polarised ferromagnetic cylinder gives rise to a cosmological magnetic field of the order $B_{now}\simeq{10^{-22}G}$. Vorticity of cylinder is used to obtain galactic magnetic fields. Magnetic fields up to $B\sim{10^{9}G}$ can be obtained from the spin density of the cylinder. If matching conditions are used cosmological magnetic fields of the order of $B\sim{10^{-16}R\frac{Gauss}{cm}}$ where $R$ is the radius of the cosmic strings. For a cosmic string with the radius of an hydrogen atom the cosmic magnetic field is $B\sim{10^{-32}Gauss}$ which is enough to seed galactic dynamos.

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L. C. Garcia de Andrade. 2014-01-12. Galactic dynamo seeds from non-superconducting spin-polarised strings. https://doi.org/10.1088/1475-7516%2F2014%2F08%2F023

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