An infrared approach to Reggeization

TL;DR

This paper introduces a new infrared-based method for analyzing Reggeization in gauge amplitudes, revealing its limitations at higher logarithmic orders and applying it to multiparticle processes.

Contribution

It develops a universal infrared singularity framework for Reggeization, extending understanding of its validity and constraints in high-energy gauge amplitudes.

Findings

Reggeization is valid at leading logarithmic order for all color exchanges.

Breakdown of Reggeization occurs at next-to-leading and next-to-next-to-leading logarithms.

The formalism constrains possible three-loop corrections to the dipole formula.

Abstract

We present a new approach to Reggeization of gauge amplitudes based on the universal properties of their infrared singularities. Using the "dipole formula", a compact ansatz for all infrared singularities of massless amplitudes, we study Reggeization of singular contributions to high-energy amplitudes for arbitrary color representations, and any logarithmic accuracy. We derive leading-logarithmic Reggeization for general cross-channel color exchanges, and we show that Reggeization breaks down for the imaginary part of the amplitude at next-to-leading logarithms and for the real part at next-to-next-to-leading logarithms. Our formalism applies to multiparticle amplitudes in multi-Regge kinematics, and constrains possible corrections to the dipole formula starting at three loops.