Unparticle & Higgs as Composites

TL;DR

This paper presents a framework where both the Higgs boson and unparticles are composite states arising from four-dimensional gauge theories, exploring their interactions, scale invariance breaking, and low-energy effective descriptions.

Contribution

It introduces a natural, hierarchy-problem-free model unifying composite Higgs and unparticles via four-fermion operators in gauge theories.

Findings

Unparticle-Higgs mixing is suppressed in this framework.

The unparticle operator near the electroweak scale has a scaling dimension between 1 and 3.

Scale invariance breaking induces an unparticle condensate acting as an infrared cutoff.

Abstract

We propose a generic framework in which the Higgs and the unparticle are both composite. The underlying theories are four dimensional, asymptotically free, nonsupersymmetric gauge theories with fermionic matter. We sketch a possible uni- fication of these two sectors at a much higher scale resembling extended technicolor models. By construction our extensions are natural, meaning that there is no hierar- chy problem. The coupling of the unparticle sector to the composite Higgs emerges as a four-fermion operator. The bilinear unparticle operator near the electroweak scale has scaling dimension in the range 1 < dU < 3. We investigate, in various ways, the breaking of scale invariance induced by the electroweak scale resulting in an unparticle condensate. The latter acts as a natural infrared cut off or hadronic scale. We give the low-energy effective theory valid near the electroweak scale. The unparticle Higgs mixing is found to be suppressed within our framework.