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arXiv · 2412.14858

Diagrammatic Derivation of Hidden Zeros and Exact Factorisation of Pion Scattering Amplitudes

Yang Li·Tianzhi Wang·Tomáš Brauner·Diederik Roest
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Abstract

Pion scattering amplitudes were recently found to vanish on specific kinematic loci, and to factorise close to these loci into a product of two lower-point amplitudes of an extended theory. We propose a diagrammatic representation of pion amplitudes that makes their vanishing on the loci manifest diagram by diagram. Moreover, we provide evidence that there is a closed-form expression for the amplitudes that generalises the near-zero factorisation in an exact manner, not only close to the loci but for all kinematic configurations. Our approach crucially relies on a novel formulation of the effective field theory of pions, in which tree-level scattering amplitudes are extracted from classical field equations for a set of covariantly conserved currents and emergent composite gauge fields.

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Yang Li, Tianzhi Wang, Tomáš Brauner, Diederik Roest. 2024-12-19. Diagrammatic Derivation of Hidden Zeros and Exact Factorisation of Pion Scattering Amplitudes. https://arxiv.org/abs/2412.14858

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