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arXiv · 2005.07154

Cluster patterns in Landau and Leading Singularities via the Amplituhedron

Ömer Gürdoğan·Matteo Parisi
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Abstract

We advance the exploration of cluster-algebraic patterns in the building blocks of scattering amplitudes in $\mathcal{N}=4$ super Yang-Mills theory. In particular we conjecture that, given a maximal cut of a loop amplitude, Landau singularities and poles of each Yangian invariant appearing in any representation of the corresponding Leading Singularities can be found together in a cluster. We check these adjacencies for all one-loop amplitudes up to 9 points. Along the way, we also prove that all (rational) N$^2$MHV Yangian invariants are cluster adjacent, confirming original conjectures.

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Ömer Gürdoğan, Matteo Parisi. 2020-05-14. Cluster patterns in Landau and Leading Singularities via the Amplituhedron. https://arxiv.org/abs/2005.07154

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