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arXiv · 1203.0198

Constructing Gravity Amplitudes from Real Soft and Collinear Factorisation

David C. Dunbar·James H. Ettle·Warren B. Perkins
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Abstract

Soft and collinear factorisations can be used to construct expressions for amplitudes in theories of gravity. We generalise the "half-soft" functions used previously to "soft-lifting" functions and use these to generate tree and one-loop amplitudes. In particular we construct expressions for MHV tree amplitudes and the rational terms in one-loop amplitudes in the specific context of N=4 supergravity. To completely determine the rational terms collinear factorisation must also be used. The rational terms for N=4 have a remarkable diagrammatic interpretation as arising from algebraic link diagrams.

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David C. Dunbar, James H. Ettle, Warren B. Perkins. 2012-05-31. Constructing Gravity Amplitudes from Real Soft and Collinear Factorisation. https://doi.org/10.1103/physrevd.86.026009

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