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arXiv · 1404.4091

Evidence for a New Soft Graviton Theorem

Freddy Cachazo·Andrew Strominger
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Abstract

The single-soft-graviton limit of any quantum gravity scattering amplitude is given at leading order by the universal Weinberg pole formula. Gauge invariance of the formula follows from global energy-momentum conservation. In this paper evidence is given for a conjectured universal formula for the finite subleading term in the expansion about the soft limit, whose gauge invariance follows from global angular momentum conservation. The conjecture is non-trivially verified for all tree-level graviton scattering amplitudes using a BCFW recursion relation. One hopes to understand this infinity of new soft relations as a Ward identity for a new superrotation Virasoro symmetry of the quantum gravity S-matrix.

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Freddy Cachazo, Andrew Strominger. 2014-06-10. Evidence for a New Soft Graviton Theorem. https://arxiv.org/abs/1404.4091

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