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arXiv · 1307.7448

Large-scale magnetic fields from inflation in teleparallel gravity

Kazuharu Bamba·Chao-Qiang Geng·Ling-Wei Luo
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Abstract

Generation of large-scale magnetic fields in inflationary cosmology is studied in teleparallelism, where instead of the scalar curvature in general relativity, the torsion scalar describes the gravity theory. In particular, we investigate a coupling of the electromagnetic field to the torsion scalar during inflation, which leads to the breaking of conformal invariance of the electromagnetic field. We demonstrate that for a power-law type coupling, the current magnetic field strength of $\sim 10^{-9}$ G on 1 Mpc scale can be generated, if the backreaction effects and strong coupling problem are not taken into consideration.

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Kazuharu Bamba, Chao-Qiang Geng, Ling-Wei Luo. 2013-07-29. Large-scale magnetic fields from inflation in teleparallel gravity. https://doi.org/10.7566/jpscp.1.013123

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