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arXiv · 0811.2221

Constraints on the Primordial Magnetic Field from $σ_8$

Dai G. Yamazaki·Kiyotomo Ichiki·Toshitaka Kajino·Grant. J. Mathews
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Abstract

A primordial magnetic field (PMF) can affect the evolution of density field fluctuations in the early universe.In this paper we constrain the PMF amplitude $B_λ$ and power spectral index $n_\mathrm{B}$ by comparing calculated density field fluctuations with observational data, i.e. the number density fluctuation of galaxies.We show that the observational constraints on cosmological density fluctuations, as parameterized by $σ_8$, lead to strong constraints on the amplitude and spectral index of the PMF.

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Dai G. Yamazaki, Kiyotomo Ichiki, Toshitaka Kajino, Grant. J. Mathews. 2008-11-13. Constraints on the Primordial Magnetic Field from $σ_8$. https://doi.org/10.1103/physrevd.78.123001

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