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arXiv · 1407.5164

Infrared singularities in multi-leg scattering amplitudes

Einan Gardi
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Abstract

I discuss the state-of-the-art knowledge of long-distance singularities in multi-leg gauge-theory scattering amplitudes and report on an on-going calculation of the three-loop soft anomalous dimension through the renormalization of correlators of semi-infinite Wilson lines. I also discuss the non-Abelian exponentiation theorem that has been recently generalised to multiple Wilson lines and demonstrate its application in computing the soft anomalous dimension. Finally, I present recent results for multiple-gluon-exchange webs and discuss their analytic structure.

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Einan Gardi. 2014-07-19. Infrared singularities in multi-leg scattering amplitudes. https://arxiv.org/abs/1407.5164

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