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arXiv · 2204.10014

Symplectic Grassmannians, dual conformal symmetry and 4-point amplitudes in 6D

Klaus Bering·Michal Pazderka
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Abstract

We investigate a new algebra-based approach of finding Grassmannian formulas for scattering amplitudes. Our prime motivation is massive amplitudes of 4D $\mathcal{N}=4$ SYM, and therefore we consider a 6D Grassmannian formula, where we can take advantage of massless kinematics. We next use symmetry arguments, and in particular, 6D dual conformal symmetry generalized to arbitrary dual conformal weights. Assuming a rational ansatz in terms of Pl\"{u}cker coordinates (i.e. minors) for the integrand, this approach leads to a set of algebraic equations. As an example, we explicitly find the solution for 4-point scattering amplitudes up to proportionality constants.

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Klaus Bering, Michal Pazderka. 2022-04-21. Symplectic Grassmannians, dual conformal symmetry and 4-point amplitudes in 6D. https://doi.org/10.1007/jhep09(2022)054

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