Gauge Theory Amplitudes, Scalar Graphs and Twistor Space

TL;DR

This paper explores a new scalar perturbation approach to calculating gauge theory amplitudes, simplifying the process compared to traditional Feynman diagrams, and discusses its applicability at tree and loop levels.

Contribution

Introduces a novel scalar perturbation formalism for gauge theory amplitudes that simplifies calculations and applies broadly at tree and possibly loop levels.

Findings

Effective scalar perturbation theory simplifies amplitude calculations.

Works in generic gauge theories, with or without supersymmetry.

Potential applicability to loop amplitudes.

Abstract

We discuss a remarkable new approach initiated by Cachazo, Svrcek and Witten for calculating gauge theory amplitudes. The formalism amounts to an effective scalar perturbation theory which in many cases offers a much simpler alternative to the usual Feynman diagrams for deriving $n$-point amplitudes in gauge theory. At tree level the formalism works in a generic gauge theory, with or without supersymmetry, and for a finite number of colours. There is also a growing evidence that the formalism works for loop amplitudes.