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arXiv · 1012.2892

Intrinsic Bispectra of Cosmic Magnetic Fields

Iain A. Brown
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Abstract

Forthcoming datasets from the Planck experiment and others are in a position to probe the CMB non-Gaussianity with higher accuracy than has yet been possible and potentially open a new window into the physics of the very early universe. However, a signal need not necessarily be inflationary in origin, and possible contaminants should be examined in detail. One such is provided by early universe magnetic fields, which can be produced by a variety of models including during an inflationary phase, at phase transitions, or seeded by cosmic defects. Should such fields have been extent in the early universe they provide a natural source of CMB non-Gaussianity. Knowledge of the CMB angular bispectrum requires the complete Fourier-space (or "intrinsic") bispectrum. In this paper I consider in detail the intrinsic bispectra of an early-universe magnetic field for a range of power-law magnetic power spectra.

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Iain A. Brown. 2011-03-25. Intrinsic Bispectra of Cosmic Magnetic Fields. https://doi.org/10.1088/0004-637x%2F733%2F2%2F83

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