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arXiv · 0906.0521

One-loop N=8 supergravity coefficients from N=4 super Yang-Mills

Panagiotis Katsaroumpas·Bill Spence·Gabriele Travaglini
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Abstract

We use supersymmetric generalised unitarity to calculate supercoefficients of box functions in the expansion of scattering amplitudes in N=8 supergravity at one loop. Recent advances have presented tree-level amplitudes in N=8 supergravity in terms of sums of terms containing squares of colour-ordered Yang-Mills superamplitudes. We develop the consequences of these results for the structure of one-loop supercoefficients, recasting them as sums of squares of N=4 Yang-Mills expressions with certain coefficients inherited from the tree-level superamplitudes. This provides new expressions for all one-loop box coefficients in N=8 supergravity, which we check against known results in a number of cases.

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Panagiotis Katsaroumpas, Bill Spence, Gabriele Travaglini. 2009-06-02. One-loop N=8 supergravity coefficients from N=4 super Yang-Mills. https://doi.org/10.1088/1126-6708%2F2009%2F08%2F096

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