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arXiv · 1209.2472

Ultraviolet Cancellations in Half-Maximal Supergravity as a Consequence of the Double-Copy Structure

Zvi Bern·Scott Davies·Tristan Dennen·Yu-tin Huang
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Abstract

We show that the double-copy structure of gravity forbids divergences in pure half-maximal (16 supercharge) supergravity at four and five points at one loop in D<8 and at two loops in D<6. We link the cancellations that render these supergravity amplitudes finite to corresponding ones that eliminate forbidden color factors from the divergences of pure nonsupersymmetric Yang-Mills theory. The vanishing of the two-loop four-point divergence in D=5 half-maximal supergravity is an example where a valid counterterm satisfying the known symmetries exists, yet is not present. We also give explicit forms of divergences in half-maximal supergravity at one loop in D=8 and at two loops in D=6.

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Zvi Bern, Scott Davies, Tristan Dennen, Yu-tin Huang. 2013-04-30. Ultraviolet Cancellations in Half-Maximal Supergravity as a Consequence of the Double-Copy Structure. https://doi.org/10.1103/physrevd.86.105014

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