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arXiv · 2303.03035

Emergent unitarity, all-loop cuts and integrations from the ABJM amplituhedron

Song He·Chia-Kai Kuo·Zhenjie Li·Yao-Qi Zhang
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Abstract

We elaborate on aspects of a new positive geometry proposed recently, which was conjectured to be the four-point amplituhedron for ABJM theory. We study generalized unitarity cuts from the geometry, and in particular we prove that (1) the four-point integrand satisfies perturbative unitarity (or optical theorem) to all loops, which follows directly from the geometry, and (2) vanishing cuts involving odd-point amplitudes follow from the ``bipartite" nature of the associated ``negative geometries", which justifies their appearance in ABJM theory. We also take a first step in integrating the forms of these negative geometries and obtain an infrared-finite quantity up to two loops, from which we extract the cusp anomalous dimension at leading order.

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Song He, Chia-Kai Kuo, Zhenjie Li, Yao-Qi Zhang. 2023-03-06. Emergent unitarity, all-loop cuts and integrations from the ABJM amplituhedron. https://doi.org/10.1007/jhep07(2023)212

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