Two-loop MHV Form Factors from the Periodic Wilson Loop

Zhenjie Li

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arXiv · 2412.17974

Two-loop MHV Form Factors from the Periodic Wilson Loop

Zhenjie Li

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Abstract

We discuss how to compute maximal-helicity-violating (MHV) form factors for the chiral part of the stress-tensor supermultiplet from periodic light-like polygon Wilson loops in planar $\mathcal N=4$ super Yang-Mills theory beyond the one-loop level. We show that the periodicity imposes path ordering on points on different edges, which explains the appearance of square roots coming from non-planar Feynman diagrams. Taking such diagrams into account, we provide the integrand of the two-loop $n$-particle MHV form factor, compute all diagrams, prove the cancellation of divergences and finally compute the two-loop 5-particle and 6-particle form factors as examples.

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Zhenjie Li. 2024-12-23. Two-loop MHV Form Factors from the Periodic Wilson Loop. https://arxiv.org/abs/2412.17974

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