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arXiv · 1410.0668

Towards one-loop SYM amplitudes from the pure spinor BRST cohomology

Carlos R. Mafra·Oliver Schlotterer
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Abstract

In this paper, we outline a method to compute supersymmetric one-loop integrands in ten-dimensional SYM theory. It relies on the constructive interplay between their cubic-graph organization and BRST invariance of the underlying pure spinor superstring description. The five- and six-point amplitudes are presented in a manifestly local form where the kinematic dependence is furnished by BRST-covariant expressions in pure spinor superspace. At five points, the local kinematic numerators are shown to satisfy the BCJ duality between color and kinematics leading to supergravity amplitudes as a byproduct. At six points, the sources of the hexagon anomaly are identified in superspace as systematic obstructions to BRST invariance. Our results are expected to reproduce any integrated SYM amplitude in dimensions $D< 8$.

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Carlos R. Mafra, Oliver Schlotterer. 2014-11-05. Towards one-loop SYM amplitudes from the pure spinor BRST cohomology. https://doi.org/10.1002/prop.201400076

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