Related papers: Do Instantons Like a Colorful Background?
We perform a mutual analysis of the topological and chiral vacuum structure of four-dimensional QCD on the lattice at finite temperature. We demonstrate that at the places where instantons are present, amplified production of quark…
We summarize recent results on the nonperturbative quark-gluon interaction in Landau gauge QCD. Our analytical analysis of the infrared behaviour of the quark-gluon vertex reveals infrared singularities, which lead to an infrared divergent…
We study the effective action for strong-coupling lattice QCD with one-component staggered fermions in the case of nonzero chemical potential and zero temperature. The structure of this action suggests that at large chemical potentials its…
I argue that in certain chiral gauge theories composite scalars associated with chiral symmetry breaking can be light (i.e. lighter than naive scaling from QCD would suggest) without any fine-tuning. These scalars will be even lighter in…
We investigate the color coherence pattern between initial and final state radiation in the presence of a QCD medium. We derive the medium-induced gluon spectrum of an "asymptotic" parton which suffers a hard scattering and subsequently…
We provide a brief review of recent progress in the study of mesons using QCD's Dyson-Schwinger equations. Along the way we touch on aspects of confinement and dynamical chiral symmetry breaking but in the main focus upon: exact results for…
We discuss the role of the U(1) axial symmetry for the phase structure of QCD at finite temperature. We expect that, above a certain critical temperature, also the U(1) axial symmetry will be (effectively) restored. We will try to see if…
We study scalar quark-anti-quark and two-quark-two-anti-quark correlation functions in the instanton liquid model. We show that the instanton liquid supports a light scalar-isoscalar (sigma) meson, and that this state is strongly coupled to…
This is a short write-up of lectures at UK Theory Institute, Swansea UK, Sept.99; and XVII School ``QCD: Perturbative or Non-perturbative?'' Lisbon,Portugal, Oct.99. The covered topic include (i) discussion of the scales at which…
The purpose of this study is to show the relations between monopoles instantons and Chiral symmetry breaking. First, in order to show the relation between instantons and monopoles, we generate configurations, adding monopoles by a monopole…
Spontaneous chiral symmetry breaking is accepted to occur in low energy hadronic physics, resulting in the several successful theorems of PCAC. On the other hand scalar confinement is suggested both by the spectroscopy of hadrons and by the…
Generalizing quantum chromodynamics (QCD) from three to arbitrarily many color degrees of freedom suggests that baryons can be described as solitons in an effective meson theory whose interaction strength decreases with the number of…
The relation between the spectral density of the QCD Dirac operator at nonzero baryon chemical potential and the chiral condensate is investigated. We use the analytical result for the eigenvalue density in the microscopic regime which…
QCD is the fundamental theory to describe the strong interaction, where quarks and gluons have the color degrees of freedom. However, a single quark or gluon can not be separated out and all observable particles are color singlet states.…
Under the assumption of Abelian dominance in QCD, we show that either color charge or chirality of quark is not conserved, when the low energy massless quark collides with QCD monopole. Because the color charge is conserved in reality, the…
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 show how to incorporate chiral symmetry breaking in the soft-wall version of the AdS/QCD model by using a modified dilaton profile and a quartic term in the bulk scalar potential. This allows one to separate the dependence on spontaneous…
A scale-invariant extension of the Standard Model with a singlet-scalar and hidden-QCD sector is studied. The scale of electroweak symmetry breaking is generated dynamically in an asymptotic-free hidden-QCD sector, and mediated by the…
Hadron-hadron scattering lengths are fine probes of our understanding of nonperturbative QCD. I discuss the status of a variety of scattering processes sensitive to the spontaneous and explicit chiral symmetry breaking of QCD, such as…
Dynamical properties of gauge theories with light flavor quarks are studied in a dual supergravity by adding a D7-brane probe into the AdS background deformed by the dilaton. By estimating the vev of flavor quark-bilinear in both the…