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arXiv · 1805.09318

Schwinger Effect by an $SU(2)$ Gauge Field during Inflation

Kaloian D. Lozanov·Azadeh Maleknejad·Eiichiro Komatsu
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Abstract

Non-Abelian gauge fields may exist during inflation. We study the Schwinger effect by an $SU(2)$ gauge field coupled to a charged scalar doublet in a (quasi) de Sitter background and the possible backreaction of the generated charged particles on the homogeneous dynamics. Contrary to the Abelian $U(1)$ case, we find that both the Schwinger pair production and the induced current decrease as the interaction strength increases. The reason for this suppression is the isotropic vacuum expectation value of the $SU(2)$ field which generates a (three times) greater effective mass for the scalar field than the $U(1)$. In the weak interaction limit, the above effect is negligible and both the $SU(2)$ and $U(1)$ cases exhibit a linear increase of the current and a constant conductivity with the interaction strength. We conclude that the Schwinger effect does not pose a threat to the dynamics of inflationary models involving an $SU(2)$ gauge field.

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Kaloian D. Lozanov, Azadeh Maleknejad, Eiichiro Komatsu. 2018-05-23. Schwinger Effect by an $SU(2)$ Gauge Field during Inflation. https://doi.org/10.1007/jhep02(2019)041

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