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arXiv · 1812.11185

Amplitudes at Infinity

Jacob L. Bourjaily·Enrico Herrmann·Jaroslav Trnka
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Abstract

We investigate the asymptotically large loop-momentum behavior of multi-loop amplitudes in maximally supersymmetric quantum field theories in four dimensions. We check residue-theorem identities among color-dressed leading singularities in $\mathcal{N}=4$ supersymmetric Yang-Mills theory to demonstrate the absence of poles at infinity of all MHV amplitudes through three loops. Considering the same test for $\mathcal{N}=8$ supergravity leads us to discover that this theory does support non-vanishing residues at infinity starting at two loops, and the degree of these poles grow arbitrarily with multiplicity. This causes a tension between simultaneously manifesting ultraviolet finiteness---which would be automatic in a representation obtained by color-kinematic duality---and gauge invariance---which would follow from unitarity-based methods.

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Jacob L. Bourjaily, Enrico Herrmann, Jaroslav Trnka. 2018-12-28. Amplitudes at Infinity. https://doi.org/10.1103/physrevd.99.066006

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