Lipatov's QCD high energy effective action: past and future

TL;DR

This paper reviews Lipatov's high energy effective action in QCD, discussing its theoretical foundations, computational applications like gluon Regge trajectory derivation, and its relation to modern frameworks such as the Color-Glass-Condensate.

Contribution

It provides a comprehensive overview of the high energy effective action, including recent developments in automatic amplitude generation and connections to other high energy QCD approaches.

Findings

Derived the gluon Regge trajectory up to 2 loops.

Discussed automatic amplitude generation methods.

Explored the relation to the Color-Glass-Condensate framework.

Abstract

In this contribution we briefly review some aspects of Lipatov's gauge invariant QCD high energy effective action. The high energy effective provides a field theory framework to systematically factorize QCD scattering amplitudes and related theories in the limit of high center of mass energies. After a short review of the underlying concepts, we address the question how the high energy effective action can be used for actual calculations. As an explicit example we review the derivation of the gluon Regge trajectory up to 2 loop. We then review two topics of current interest: automatic amplitude generation of high energy effective action amplitudes and a discussion of the relation between the so-called Color-Glass-Condensate framework and the high energy effective action.