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arXiv · 1108.0151

Large-scale magnetic fields from inflation due to a $CPT$-even Chern-Simons-like term with Kalb-Ramond and scalar fields

Kazuharu Bamba·C. Q. Geng·S. H. Ho·W. F. Kao
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Abstract

We investigate the generation of large-scale magnetic fields due to the breaking of the conformal invariance in the electromagnetic field through the $CPT$-even dimension-six Chern-Simons-like effective interaction with a fermion current by taking account of the dynamical Kalb-Ramond and scalar fields in inflationary cosmology. It is explicitly demonstrated that the magnetic fields on 1Mpc scale with the field strength of $\sim 10^{-9}$G at the present time can be induced.

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Kazuharu Bamba, C. Q. Geng, S. H. Ho, W. F. Kao. 2012-03-26. Large-scale magnetic fields from inflation due to a $CPT$-even Chern-Simons-like term with Kalb-Ramond and scalar fields. https://doi.org/10.1140/epjc%2Fs10052-012-1978-1

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