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Microwave Background Anisotropies from Alfven waves

Ruth Durrer·Tina Kahniashvili·Andrew Yates
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Abstract

We investigate microwave background anisotropies in the presence of primordial magnetic fields. We show that a homogeneous field with fixed direction can amplify vector perturbations. We calculate the correlations of $δT/T$ explicitly and show that a large scale coherent field induces correlations between $a_{\ell-1,m}$ and $a_{\ell+1,m}$. We discuss constraints on amplitude and spectrum of a primordial magnetic field imposed by observations of CMB anisotropies.

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Ruth Durrer, Tina Kahniashvili, Andrew Yates. 1998-07-09. Microwave Background Anisotropies from Alfven waves. https://doi.org/10.1103/physrevd.58.123004

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