Scattering equations, supergravity integrands, and pure spinors

Tim Adamo; Eduardo Casali

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arXiv · 1502.06826

Scattering equations, supergravity integrands, and pure spinors

Tim Adamo·Eduardo Casali

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Abstract

The tree-level S-matrix of type II supergravity can be computed in scattering equation form by correlators in a worldsheet theory analogous to a chiral, infinite tension limit of the pure spinor formalism. By defining a non-minimal version of this theory, we give a prescription for computing correlators on higher genus worldsheets which manifest space-time supersymmetry. These correlators are conjectured to provide the loop integrands of supergravity scattering amplitudes, supported on the scattering equations. We give non-trivial evidence in support of this conjecture at genus one and two with four external states. Throughout, we find a close correspondence with the pure spinor formalism of superstring theory, particularly regarding regulators and zero-mode counting.

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Tim Adamo, Eduardo Casali. 2015-02-24. Scattering equations, supergravity integrands, and pure spinors. https://arxiv.org/abs/1502.06826

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