The Conformal Window of deformed CFT's in the planar limit

TL;DR

This paper explores how double-trace deformations affect conformal field theories in the planar limit, revealing a conformal window, a resonance linked to a dilaton, and a phase transition with implications for unparticle physics.

Contribution

It introduces a detailed analysis of the conformal window in deformed CFTs, including the identification of a resonance and a phase transition, and applies these findings to strongly coupled gauge theories.

Findings

Identification of a conformal window with a non-trivial RG flow

Discovery of a resonance associated with a dilaton pole

Analysis of a conformal phase transition and its phenomenological implications

Abstract

We discuss in the planar approximation the effect of double-trace deformations on CFT's. We show that this large class of models posses a conformal window describing a non-trivial flow between two fixed points of the renormalization group, and reveal the presence of a resonance which we associate to the remnant of a dilaton pole. As the conformal window shrinks to zero measure the theory undergoes a conformal phase transition separating a symmetric from a nonsymmetric phase. The recently conjectured strongly coupled branch of non-supersymmetric, non-abelian gauge theories with a large number of flavors is analyzed in light of these results, and a model for the strong branch is proposed. Some phenomenological implications in the context of unparticle physics are also emphasized.