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arXiv · 1909.04229

Lessons from $T^{\mu}_{~ \mu}$ on inflation models: two-loop renormalization of $\eta$ in the scalar QED

Ayuki Kamada·Takumi Kuwahara
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Abstract

A non-minimal coupling $\eta$ has been attracting growing interest particularly in the context of inflation models, though its quantum nature is not clear yet. We study the renormalization of a non-minimal coupling in the scalar quantum electrodynamics (QED). We find ${\it no}$ inhomogeneous term of the renormalization group equation (RGE) at the two-loop level. This is similar to other theories, where an inhomogeneous term of the RGE appears only at a higher-loop order: e.g., four-loop order in $\lambda \phi^{4}$ theory.

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Ayuki Kamada, Takumi Kuwahara. 2019-09-10. Lessons from $T^{\mu}_{~ \mu}$ on inflation models: two-loop renormalization of $\eta$ in the scalar QED. https://doi.org/10.1103/physrevd.103.116001

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