Conformal Dynamics for TeV Physics and Cosmology

Abstract

We introduce the topic of dynamical breaking of the electroweak symmetry and its link to unparticle physics and cosmology. The knowledge of the phase diagram of strongly coupled theories plays a fundamental role when trying to construct viable extensions of the standard model (SM). Therefore we present the state-of-the-art of the phase diagram for SU , Sp and SO gauge theories with fermionic matter transforming according to arbitrary representations of the underlying gauge group. We summarize several analytic methods used recently to acquire information about these gauge theories. We also provide new results for the phase diagram of the generalized Bars-Yankielowicz and Georgi-Glashow chiral gauge theories. These theories have been used for constructing grand unified models and have been the template for models of extended technicolor interactions. To gain information on the phase diagram of chiral gauge theories we will introduce a novel all orders beta function for chiral gauge theories. This permits the first unified study of all nonsupersymmetric gauge theories with fermionic matter representation both chiral and non-chiral. To the best of our knowledge the phase diagram of these complex models appears here for the first time. We will introduce recent extensions of the SM featuring minimal conformal gauge theories known as minimal walking models. Finally we will discuss the electroweak phase transition at nonzero temperature for models of dynamical electroweak symmetry breaking.

Light dilaton at fixed points and ultra light scale super-Yang–Mills

“…Besides the possibility of infrared fixed points recently it has been discovered that nonsupersymmetric gauge theories with fermionic matter at large number of flavors develop ultraviolet fixed points [10]. Furthermore, as soon as it was discovered that theories with an extremely low number of matter flavors were able to lead to large distance conformality and potentially become excellent candidates of models of dynamical electroweak symmetry breaking, the question whether these theories could feature light composite scalars was addressed in [14][15][16]. These papers rekindled the long debate on the existence of a light scalar compared to the intrinsic scale of the theory.…”

“…A variety of arguments has been used in favor of the existence of a light scalar, not associated to Goldstone bosons linked to the spontaneous breaking of global symmetries. Furthermore, there has been used a number of methods ranging from the use of the saturation of the trace and axial anomaly [18] to supersymmetry [14,[19][20][21], alternative large N limits [16,22] as well as gauge-gauge duality [23][24][25][26]. Other interesting attempts to investigate the dynamics associated to light scalars in near conformal field theories appeared in the literature [27][28][29][30].…”

Mixed dark matter from technicolor

“…A review of these models and the phase diagram of strongly coupled theories can be found in Ref. [37]. A relevant point is that the technicolor dynamics is strongly modified by the new interactions necessary to give masses to SM fermions [38] and the interplay between these two sectors leads to an entirely new class of models, constraints on which were discussed in Ref.…”

Chiral symmetry breaking and confinement: separating the scales

“…In this section we will move to considering gauge theories with the matter fields distributed in two distinct and inequivalent representations of the gauge group. Such theories are starting to become of interest because they may play role in composite higgs [64], composite dark matter [65] and composite inflation [66] models. As a result there are already some lattice simulation of such theories.…”