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arXiv · 1309.2498

The Ultraviolet Properties of N=4 Supergravity at Four Loops

Zvi Bern·Scott Davies·Tristan Dennen·Alexander V. Smirnov·Vladimir A. Smirnov
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Abstract

We demonstrate that pure N=4 supergravity is ultraviolet divergent at four loops. The form of the divergence suggests that it is due to the rigid U(1) duality-symmetry anomaly of the theory. This is the first known example of an ultraviolet divergence in a pure ungauged supergravity theory in four dimensions. We use the duality between color and kinematics to construct the integrand of the four-loop four-point amplitude, whose ultraviolet divergence is then extracted by standard integration techniques.

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Zvi Bern, Scott Davies, Tristan Dennen, Alexander V. Smirnov, Vladimir A. Smirnov. 2013-12-09. The Ultraviolet Properties of N=4 Supergravity at Four Loops. https://doi.org/10.1103/physrevlett.111.231302

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