The Lagrangian origin of MHV rules

TL;DR

This paper derives MHV rules from a canonical transformation of the Yang-Mills action, using light-front quantisation, and extends the approach to include massless fermions.

Contribution

It introduces a canonical transformation that naturally produces MHV rules from the Yang-Mills action, incorporating fermions.

Findings

The transformation reproduces MHV rules in Feynman diagrams.

Off-shell continuation arises naturally from light-front quantisation.

The method extends to massless fermions.

Abstract

We construct a canonical transformation that takes the usual Yang-Mills action into one whose Feynman diagram expansion generates the MHV rules. The off-shell continuation appears as a natural consequence of using light-front quantisation surfaces. The construction extends to include massless fermions.