T-Parity Violation by Anomalies

TL;DR

This paper demonstrates that T-parity in Little Higgs models is generally violated by anomalies, affecting the stability and phenomenology of these theories, with implications for dark matter and electroweak precision tests.

Contribution

It provides a detailed analysis of T-parity violation due to anomalies in Little Higgs models, deriving minimal topological interactions for a specific scheme and extending results to more general models.

Findings

T-parity is generally broken by anomalies in Little Higgs theories.

Derived minimal topological interactions for a specific SU(3) x SU(3)/SU(3) model.

Results applicable to various extended Little Higgs models.

Abstract

Little Higgs theories often rely on an internal parity ("T-parity'') to suppress non-standard electroweak effects or to provide a dark matter candidate. We show that such a symmetry is generally broken by anomalies, as described by the Wess-Zumino-Witten term. We study a simple SU(3) x SU(3)/SU(3) Little Higgs scheme where we obtain a minimal form for the topological interactions of a single Higgs field. The results apply to more general models, including [SU(3) x SU(3)/SU(3)]^4, SU(5)/SO(5), and SU(6)/Sp(6).