The Polynomial Form of the Scattering Equations is an H-Basis
Jorrit Bosma, Mads Sogaard, Yang Zhang
TL;DR
The paper proves that the polynomial form of the CHY scattering equations, encoded by $h_m$ for $1\le m\le n-3$, constitutes a Macaulay $H$-basis for the zero-dimensional ideal they generate. This enables a purely linear-algebraic integrand reduction with a sharp degree bound $d^*=(n-3)(n-4)/2$, and a streamlined computation of global residues via either the Bezoutian duality or a direct $H$-basis approach. A key consequence is that the global residue is determined by a single leading coefficient, consistent with Euler–Jacobi vanishing and the existence of a constant in the dual basis. These results significantly simplify CHY amplitude calculations and hint at deeper algebraic structure, with potential analytic expressions for residues and loop-level generalizations forthcoming.
Abstract
We prove that the polynomial form of the scattering equations is a Macaulay H-basis. We demonstrate that this H-basis facilitates integrand reduction and global residue computations in a way very similar to using a Gröbner basis, but circumvents the heavy computation of the latter. As an example, we apply the H-basis to prove the conjecture that the dual basis of the polynomial scattering equations must contain one constant term.
