A first look at hexagonal bootstrap for QCD scattering amplitudes

by Qinglin Yang (Max Planck Institute for Physics)

Monday 13 Oct 2025, 14:00 → 15:00 Europe/Zurich

4/3-006 - TH Conference Room (CERN)

In this talk, we present a bootstrap construction of planar two-loop six-point scattering amplitudes in QCD theory, focusing on their maximal transcendental weight components. From an analysis of on-shell diagrams, we identify a complete and conformally-invariant set of leading singularities. Combining these results with recent advances in understanding the relevant hexagonal function space from canonical differential equation, we can uniquely determine the maximal weight parts of helicity amplitudes by imposing correct physical limits. We especially present a detailed picture of two-loop six-point amplitudes at the symbol level in pure Yang–Mills theory. It also reveals a remarkably small and tightly constrained function alphabet, hinting at a deeper organizing principle similar to that observed in maximally 
supersymmetric Yang–Mills theory.

CERN v3.pdf

Recording