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arXiv · 1506.02864

Photon polarization tensor on deformed spacetime: A four-photon-tadpole contribution

Raul Horvat·Josip Trampetic·Jiangyang You
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Abstract

In this contribution to the Proceedings of the Corfu Summer Institute 2015 we present our study on photon self-interaction in the deformed U(1) gauge field theory defined via Seiberg-Witten map. We derive the theta-exact expressions for the four photon self-coupling in this theory with a large number of gauge symmetry inspired freedom parameters included. The physical effect of four photon self-coupling is accessed by its contribution to photon polarization tensor via 1-loop four-photon-tadpole-diagram. The four-photon tadpole diagram consists the same tensorial structures as the photon self-interacting bubble diagram we studied before, with however only quadratically IR divergent coefficients. We show that there exists a unique combination of gauge symmetry inspired freedoms which induces full quadratic IR divergence cancellation for arbitrary noncommutative parameter theta once the photon self-interacting bubble and tadpole diagrams are summed over.

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Raul Horvat, Josip Trampetic, Jiangyang You. 2015-06-09. Photon polarization tensor on deformed spacetime: A four-photon-tadpole contribution. https://arxiv.org/abs/1506.02864

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