Resumming Photon Loops for Inflationary Gravity

A. J. Foraci; R. P. Woodard

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arXiv · 2412.11022

Resumming Photon Loops for Inflationary Gravity

A. J. Foraci·R. P. Woodard

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Abstract

A previous calculation of the 1-loop photon contribution to the graviton self-energy on de Sitter background is considered. We first show that there is no local obstacle to conservation, unlike the contribution from a loop of massless, minimally coupled scalars. This is correlated to the absence of an Eddington ($R^2$) counterterm and to the vanishing of the stress tensor when the photon in integrated out in the presence of a constant graviton field. We also show that there is a secularly growing 1-loop contribution to the electric components of the Weyl tensor for plane wave gravitons. Its coefficient agrees with that of the secular 1-loop correction to the Newtonian potential, and both can be resummed using a variant of the renormalization group.

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A. J. Foraci, R. P. Woodard. 2024-12-15. Resumming Photon Loops for Inflationary Gravity. https://arxiv.org/abs/2412.11022

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