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arXiv · 1207.3220

Graphs, determinants and gravity amplitudes

Bo Feng·Song He
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Abstract

We apply the matrix-tree theorem to establish a link between various diagrammatic and determinant expressions, which naturally appear in scattering amplitudes of gravity theories. Using this link we are able to give a general graph-theoretical formulation for the tree-level maximally-helicity-violated gravity amplitudes. Furthermore, we use the link to prove two identities for half-soft functions of gravity amplitudes. Finally we recast the diagrammatic formulation of one-loop rational part of $\mathcal{N}=4$ supergravity into a matrix form.

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Bo Feng, Song He. 2012-07-13. Graphs, determinants and gravity amplitudes. https://doi.org/10.1007/jhep10(2012)121

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