Jumping Out of the Light-Higgs Conformal Window

TL;DR

This paper studies the nature of the conformal phase transition in gauge theories with Higgs-like particles, revealing it is typically a jump transition with specific spectral implications, and provides a calculable model illustrating this behavior.

Contribution

It demonstrates that the conformal phase transition at the Higgs conformal window boundary is a jumping transition and offers conditions and a model for this phenomenon.

Findings

The phase transition is generally a jump, not smooth.

The spectrum changes discontinuously at the transition.

A perturbative model exhibiting a jumping conformal transition is presented.

Abstract

We investigate generic properties of the conformal phase transition in gauge theories featuring Higgs-like fundamental particles. These theories provide an excellent arena to properly investigate conformal dynamics and discover novel features. We show that the phase transition at the boundary of the Higgs conformal window is not smooth but a jumping one for the known perturbative examples. In addition the general conditions under which the transition is either jumping or smooth are provided. Jumping implies that the massive spectrum of the theory will jump at the phase transition. It, however, still allows for one of the states, the would be dilaton of the theory, to be lighter than the heaviest states in the broken phase. Finally we exhibit a calculable Higgs model in which we can, in perturbation theory, determine the Higgs conformal window, the spectrum in the conformally broken phase and demonstrate it to possess a jumping type conformal phase transition.