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arXiv · hep-th/0701187

Recursion Relations for One-Loop Gravity Amplitudes

Andreas Brandhuber·Simon McNamara·Bill Spence·Gabriele Travaglini
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Abstract

We study the application of recursion relations to the calculation of finite one-loop gravity amplitudes. It is shown explicitly that the known four, five, and six graviton one-loop amplitudes for which the external legs have identical outgoing helicities, and the four graviton amplitude with helicities (-,+,+,+) can be derived from simple recursion relations. The latter amplitude is derived by introducing a one-loop three-point vertex of gravitons of positive helicity, which is the counterpart in gravity of the one-loop three-plus vertex in Yang-Mills. We show that new issues arise for the five point amplitude with helicities (-,+,+,+,+), where the application of known methods does not appear to work, and we discuss possible resolutions.

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Andreas Brandhuber, Simon McNamara, Bill Spence, Gabriele Travaglini. 2007-01-30. Recursion Relations for One-Loop Gravity Amplitudes. https://doi.org/10.1088/1126-6708%2F2007%2F03%2F029

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