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arXiv · 1203.1689

Photon-Graviton Amplitudes from the Effective Action

F. Bastianelli·O. Corradini·J. M. Davila·C. Schubert
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Abstract

We report on the status of an ongoing effort to calculate the complete one-loop low-energy effective actions in Einstein-Maxwell theory with a massive scalar or spinor loop, and to use them for obtaining the explicit form of the corresponding M-graviton/N-photon amplitudes. We present explicit results for the effective actions at the one-graviton four-photon level, and for the amplitudes at the one-graviton two-photon level. As expected on general grounds, these amplitudes relate in a simple way to the corresponding four-photon amplitudes. We also derive the gravitational Ward identity for the 1PI one-graviton -- N photon amplitude.

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F. Bastianelli, O. Corradini, J. M. Davila, C. Schubert. 2012-03-08. Photon-Graviton Amplitudes from the Effective Action. https://doi.org/10.1134/s1063779612050036

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