Little Higgs Models: New Approaches to the Hierarchy Problem
Jay G. Wacker
TL;DR
Little Higgs models address the hierarchy problem by treating the Higgs as a pseudo-Goldstone boson of an approximate global symmetry, delaying dangerous radiative corrections. The framework uses gauged non-linear sigma models and theory-space constructions with collective symmetry breaking to push one-loop quadratic divergences to two-loop order, resulting in a calculable low-energy spectrum that includes a two-Higgs-doublet sector and TeV-scale states. The Minimal Moose provides a concrete realization with two gauge groups, four link fields, and plaquettes that yield radiative EWSB while canceling divergences via a top-sector with a vector-like fermion, enabling a consistent view up to a 10–30 TeV cutoff and motivating testable collider signatures and UV-completion questions.
Abstract
In this note we present a review of the little Higgs models that stabilize the electroweak by realizing the Standard Model Higgs as a pseudo-Goldstone boson.