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arXiv · 0907.3703

A Model of Universe Anisotropization

Leonardo Campanelli
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Abstract

The presence of a nonconformally invariant term in the photon sector of the Lorentz-violating extension of Standard Model of particle physics, the "Kostelecký term" $\mathcal{L}_K \propto (k_F)_{αβμν} F^{αβ} F^{\m ν}$, enables a superadiabatic amplification of magnetic vacuum fluctuations during de Sitter inflation. For a particular form of the external tensor $k_F$ that parameterizing Lorentz violation, the generated field possesses a planar symmetry at large cosmological scales and can have today an intensity of order of nanogauss for a wide range of values of parameters defining inflation. This peculiar magnetic field could account for the presently-observed galactic magnetic fields and induces a small anisotropization of the universe at cosmological scales. The resulting Bianchi I model could explain the presumedly low-quadrupole power in the Cosmic Microwave Background radiation.

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Leonardo Campanelli. 2009-09-17. A Model of Universe Anisotropization. https://doi.org/10.1103/physrevd.80.063006

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