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arXiv · 2503.09571

Kinematic Stratifications

Veronica Calvo Cortes·Hadleigh Frost·Bernd Sturmfels
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Abstract

We study stratifications of regions in the space of symmetric matrices. Their points are Mandelstam matrices for momentum vectors in particle physics. Kinematic strata in these regions are indexed by signs and rank two matroids. Matroid strata of Lorentzian quadratic forms arise when all signs are non-negative. We characterize the posets of strata, for massless and massive particles, with and without momentum conservation.

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Veronica Calvo Cortes, Hadleigh Frost, Bernd Sturmfels. 2026-03-03. Kinematic Stratifications. https://arxiv.org/abs/2503.09571

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