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arXiv · hep-th/0702112

Three-Loop Superfiniteness of N=8 Supergravity

Z. Bern·J. J. Carrasco·L. J. Dixon·H. Johansson·D. A. Kosower·R. Roiban
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Abstract

We construct the three-loop four-point amplitude of N=8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments, render its degree of divergence in D dimensions to be no worse than that of N=4 super-Yang-Mills theory -- a finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N=8 supergravity may be a perturbatively finite theory of quantum gravity.

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Z. Bern, J. J. Carrasco, L. J. Dixon, H. Johansson, D. A. Kosower, R. Roiban. 2007-07-11. Three-Loop Superfiniteness of N=8 Supergravity. https://doi.org/10.1103/physrevlett.98.161303

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