Related papers: QCD with an Infrared Fixed Point -- Pion Sector
Following previous work we further explore the possibility that the chirally broken phase of gauge theories admits an infrared fixed point interpretation. The slope of the $\beta$ function, $\beta'_*$, is found to vanish at the infrared…
We investigate the chiral dynamics of gauge theories developing an infrared stable fixed point. We determine the dependence of the bilinear fermion condensate on the underlying fermion mass and its anomalous dimension. We introduce the…
We consider the problem of soft scattering for the analogue of pion states in gauge-fermion theories which approach a conformal fixed point in the infrared limit. Introducing a fermion mass into such a theory will explicitly break both…
We analyze the existence of a dilaton in gauge theories with approximate infrared conformal symmetry. To the extent that these theories are governed in the infrared by an approximate fixed point (walking), the explicit breaking of the…
Recently, we developed an effective theory of pions and a light dilatonic meson for gauge theories with spontaneously broken chiral symmetry that are close to the conformal window. The pion mass term in this effective theory depends on an…
Using lattice simulations, we study the extent of the conformal window for an $\text{SU}(3)$ gauge theory with $N_f$ Dirac fermions in the fundamental representation. We present evidence that the infrared behavior is conformal for $12 \leq…
We investigate the gauge dynamics of nonsupersymmetric SU(N) gauge theories featuring the simultaneous presence of fermionic matter transforming according to two distinct representations of the underlying gauge group. We bound the regions…
We investigate the conformal window of four-dimensional gauge theories with fermionic matter fields in multiple representations. Of particularly relevant examples are the ultra-violet complete models with fermions in two distinct…
The infrared effective theory of adjoint QCD with one Dirac flavour is still under debate. The theory could be confining, conformal, or with a massless fermion in the infrared. The study of chiral symmetry seems to be important to answer…
We review the failure of lowest order chiral $SU(3)_L \times SU(3)_R$ perturbation theory $\chi$PT$_3$ to account for amplitudes involving the $f_0(500)$ resonance and $O(m_K)$ extrapolations in momenta. We summarize our proposal to replace…
We compute the running of the coupling in SU(2) gauge theory with six fermions in fundamental representation of the gauge group. We establish an infrared stable fixed point at strong coupling and measure also the anomalous dimension of the…
We investigate the properties of near-conformal dynamics in a sector of large charge when approaching the lower boundary of the conformal window from the chirally broken phase. To elucidate our approach we use the time-honored example of…
We compute the spectrum of SU(2) gauge theory with two, four or six Dirac fermions in the fundamental representation of the gauge group. We investigate the scaling of the meson masses as a function of the quark mass when approaching the…
We study four-dimensional gauge theories coupled to fermions in the fundamental and meson-like scalars. All requisite beta functions are provided for general gauge group and fermion representation. In the regime where asymptotic freedom is…
We present a simplified holographic model of chiral symmetry breaking in gauge theory. The chiral condensate is represented by a single scalar field in AdS, with the gauge dynamics input through radial dependence of its mass, representing…
Composite Higgs models must exhibit very different dynamics from quantum chromodynamics (QCD) regardless whether they describe the Higgs boson as a dilatonlike state or a pseudo-Nambu-Goldstone boson. Large separation of scales and large…
I propose to change the sign of the dilaton in the infrared~(IR) soft-wall AdS/QCD model, in order to implement confinement. The deformed model exhibits interesting properties, especially in describing chiral symmetry breaking. The…
{We present the results of a numerical investigation of SU(2) gauge theory with $N_f=3/2$ flavours of fermions, corresponding to 3 Majorana fermions, which transform in the adjoint representation of the gauge group. At two values of the…
We revisit standard arguments for hyperscaling of the spectrum when a non-zero fermion mass is introduced to a gauge-fermion theory which is conformal in the infrared limit. With some general assumptions, we argue that the induced…
We confront Cardy's suggested c-function for four-dimensional field theories with the spontaneous breaking of chiral symmetries in asymptotically free vectorlike gauge theories with fermions transforming according to different…