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arXiv · 1811.10398

All two-loop MHV remainder functions in multi-Regge kinematics

Vittorio Del Duca·Claude Duhr·Falko Dulat·Brenda Penante
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Abstract

We introduce a method to extract the symbol of the coefficient of $(2\pi i)^2$ of MHV remainder functions in planar N=4 Super Yang-Mills in multi-Regge kinematics region directly from the symbol in full kinematics. At two loops this symbol can be uplifted to the full function in a unique way, without any beyond-the-symbol ambiguities. We can therefore determine all two-loop MHV amplitudes at function level in all kinematic regions with different energy signs in multi-Regge kinematics. We analyse our results and we observe that they are consistent with the hypothesis of a contribution from the exchange of a three-Reggeon composite state starting from two loops and eight points in certain kinematic regions.

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Vittorio Del Duca, Claude Duhr, Falko Dulat, Brenda Penante. 2018-11-26. All two-loop MHV remainder functions in multi-Regge kinematics. https://doi.org/10.1007/jhep01(2019)162

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