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arXiv · 1607.07041

Stealth magnetic field in de Sitter spacetime

Shinji Mukohyama
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Abstract

In the context of a U(1) gauge theory non-minimally coupled to scalar-tensor gravity, we find a cosmological attractor solution that represents a de Sitter universe with a homogeneous magnetic field. The solution fully takes into account backreaction of the magnetic field to the geometry and the scalar field. Such a solution is made possible by scaling-type global symmetry and fine-tuning of two parameters of the theory. If the fine-tuning is relaxed then the solution is deformed to an axisymmetric Bianchi type-I universe with constant curvature invariants, a homogeneous magnetic field and a homogeneous electric field. Implications to inflationary magnetogenesis are briefly discussed.

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Shinji Mukohyama. 2016-07-24. Stealth magnetic field in de Sitter spacetime. https://doi.org/10.1103/physrevd.94.121302

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