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arXiv · 1905.05151

Two-loop n-point anomalous amplitudes in N=4 supergravity

Zvi Bern·David Kosower·Julio Parra-Martinez
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Abstract

We compute the anomalous two-loop four-point amplitudes in N=4 pure supergravity, using unitarity and the double-copy construction. We also present all terms determined by four-dimensional cuts in two all-multiplicity two-loop anomalous superamplitudes. This result provides the first two-loop n-point gravity amplitude, up to a class of undetermined rational terms, which are absent at four points. We show that a recently proposed finite counterterm cancels these amplitudes to this order. We argue that the counterterm does not spoil the three-loop finiteness of anomalous amplitudes in the N=4 theory.

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Zvi Bern, David Kosower, Julio Parra-Martinez. 2019-05-13. Two-loop n-point anomalous amplitudes in N=4 supergravity. https://doi.org/10.1098/rspa.2019.0722

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