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arXiv · 1907.01053

Tropical Grassmannians, cluster algebras and scattering amplitudes

James Drummond·Jack Foster·Ömer Gürdoğan·Chrysostomos Kalousios
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Abstract

We provide a cluster-algebraic approach to the computation of the recently introduced generalised biadjoint scalar amplitudes related to Grassmannians ${\rm Gr}(k,n)$. A finite cluster algebra provides a natural triangulation for the tropical Grassmannian whose volume computes the scattering amplitudes. Using this method one can construct the entire colour-ordered amplitude via mutations starting from a single term.

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James Drummond, Jack Foster, Ömer Gürdoğan, Chrysostomos Kalousios. 2019-07-01. Tropical Grassmannians, cluster algebras and scattering amplitudes. https://doi.org/10.1007/jhep04(2020)146

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