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arXiv · 2512.22092

Flat space Fermionic Wave-function coefficients

Bo-Ting Chen·Wei-Ming Chen·Yu-tin Huang·Zi-Xun Huang·Yohan Liu
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Abstract

In this work we analyze the analytic structure of tree-level flat-space wavefunction coefficients (WFCs), with particular attention to fermionic operators, and derive cutting rules for internal-fermion lines. Building on these results, we set up an iterative procedure that, starting from the flat-space S-matrix, reconstructs the 3- and 4-point WFCs with the correct partial- and total-energy poles and satisfying the requisite cutting rules. Consequently, the "four-particle test" for flat-space WFCs imposes no additional constraints beyond the consistency of the flat-space S-matrix.

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Bo-Ting Chen, Wei-Ming Chen, Yu-tin Huang, Zi-Xun Huang, Yohan Liu. 2025-12-26. Flat space Fermionic Wave-function coefficients. https://arxiv.org/abs/2512.22092

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