Trilinear Gauge Interactions in Extensions of the Standard Model and Unitarity

TL;DR

This paper explores anomaly poles in gauge theories, their impact on unitarity at high energies, and how axion exchange can restore unitarity, with implications for extensions of the Standard Model.

Contribution

It provides a detailed analysis of anomaly vertices, compares different representations, and discusses the role of axions in maintaining unitarity in extended gauge theories.

Findings

Anomaly poles cause unitarity violation at high energies.

Axion exchange restores unitarity in these theories.

The work clarifies the properties of anomaly vertices in different representations.

Abstract

We summarize recent work on the characterization of anomaly poles in connection with the field-theory interpretation of the Green-Schwarz mechanism of anomaly cancellation and on their effective field theories, stressing on the properties of the anomaly vertex in two representations, the Rosenberg and the Longitudinal/Transverse. The presence of polar amplitudes in these theories causes a violation of unitarity at high energy which is cured by the exchange of the axion. We comment on the possible physical implications of this mechanism.