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arXiv · hep-th/0501137

Inherited Twistor-Space Structure of Gravity Loop Amplitudes

Zvi Bern·N. E. J. Bjerrum-Bohr·David C. Dunbar
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Abstract

At tree-level, gravity amplitudes are obtainable directly from gauge theory amplitudes via the Kawai, Lewellen and Tye closed-open string relations. We explain how the unitarity method allows us to use these relations to obtain coefficients of box integrals appearing in one-loop N=8 supergravity amplitudes from the recent computation of the coefficients for N=4 super-Yang-Mills non-maximally-helicity-violating amplitudes. We argue from factorisation that these box coefficients determine the one-loop N=8 supergravity amplitudes, although this remains to be proven. We also show that twistor-space properties of the N=8 supergravity amplitudes are inherited from the corresponding properties of N=4 super-Yang-Mills theory. We give a number of examples illustrating these ideas.

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Zvi Bern, N. E. J. Bjerrum-Bohr, David C. Dunbar. 2005-03-03. Inherited Twistor-Space Structure of Gravity Loop Amplitudes. https://doi.org/10.1088/1126-6708%2F2005%2F05%2F056

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