English

A new recursion relation for tree-level NLSM amplitudes based on hidden zeros

High Energy Physics - Theory 2026-05-05 v2

Abstract

In this note, we propose a novel BCFW-like recursion relation for tree-level non-linear sigma model (NLSM) amplitudes, which circumvents the computation of boundary terms by exploiting the recently discovered hidden zeros. Using this recursion, we reproduce three remarkable features of tree-level NLSM amplitudes: (i) the Adler zero, (ii) the δ\delta-shift construction, which generates NLSM amplitudes from Tr(ϕ3){\rm Tr}(\phi^3) amplitudes, and (iii) the universal expansion of NLSM amplitudes into bi-adjoint scalar amplitudes. Our results demonstrate that the hidden zeros, combined with standard factorization on physical poles, uniquely determine all tree-level NLSM amplitudes.

Keywords

Cite

@article{arxiv.2508.12894,
  title  = {A new recursion relation for tree-level NLSM amplitudes based on hidden zeros},
  author = {Xiaodi Li and Kang Zhou},
  journal= {arXiv preprint arXiv:2508.12894},
  year   = {2026}
}

Comments

25 pages, 3 figures

R2 v1 2026-07-01T04:54:46.125Z