Calculating Scattering Amplitudes Efficiently

TL;DR

This paper reviews advanced techniques for efficiently computing perturbative scattering amplitudes in gauge theories, focusing on decomposition methods, analytic properties, and various computational tools to improve calculation speed and accuracy.

Contribution

It introduces a comprehensive overview of methods leveraging color, helicity, and analytic properties to enhance the efficiency of scattering amplitude calculations in QCD.

Findings

Improved computational efficiency for multi-parton amplitudes.

Enhanced understanding of analytic structures like cuts and poles.

Effective use of recursion relations and supersymmetric rearrangements.

Abstract

We review techniques for more efficient computation of perturbative scattering amplitudes in gauge theory, in particular tree and one-loop multi-parton amplitudes in QCD. We emphasize the advantages of (1) using color and helicity information to decompose amplitudes into smaller gauge-invariant pieces, and (2) exploiting the analytic properties of these pieces, namely their cuts and poles. Other useful tools include recursion relations, special gauges and supersymmetric rearrangements.