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arXiv · 1503.02663

2D Kac-Moody Symmetry of 4D Yang-Mills Theory

Temple He·Prahar Mitra·Andrew Strominger
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Abstract

Scattering amplitudes of any four-dimensional theory with nonabelian gauge group $\mathcal G$ may be recast as two-dimensional correlation functions on the asymptotic two-sphere at null infinity. The soft gluon theorem is shown, for massless theories at the semiclassical level, to be the Ward identity of a holomorphic two-dimensional $\mathcal G$-Kac-Moody symmetry acting on these correlation functions. Holomorphic Kac-Moody current insertions are positive helicity soft gluon insertions. The Kac-Moody transformations are a $CPT$ invariant subgroup of gauge transformations which act nontrivially at null infinity and comprise the four-dimensional asymptotic symmetry group.

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Temple He, Prahar Mitra, Andrew Strominger. 2016-10-18. 2D Kac-Moody Symmetry of 4D Yang-Mills Theory. https://doi.org/10.1007/jhep10(2016)137

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