Analytic Scattering Amplitudes for QCD

TL;DR

This paper explores the use of analytic continuation of QCD scattering amplitudes in complex momentum space to derive recursion relations, simplifying multi-gluon amplitude calculations within the space-cone gauge.

Contribution

It introduces a method combining analytic continuation, the largest time equation, and gauge invariance to derive recursion relations for QCD amplitudes.

Findings

Derivation of recursion relations for multi-gluon scattering amplitudes.

Simplification of amplitude calculations in the space-cone gauge.

Insights into factorization and unitarity through complexified momenta.

Abstract

By analytically continuing QCD scattering amplitudes through specific complexified momenta, one can study and learn about the nature and the consequences of factorization and unitarity. In some cases, when coupled with the largest time equation and gauge invariance requirement, this approach leads to recursion relations, which greatly simplify the construction of multi-gluon scattering amplitudes. The setting for this discussion is in the space-cone gauge.