Related papers: Instantons and quark zero modes in AdS/QCD
The main objective of this work is to explore the evolution in the structure of the quark-anti-quark bound states in going down in the chirally restored phase from the so-called "zero binding points" $T_{zb}$ to the full (unquenched) QCD…
We prove the existence of zero modes of massless quarks in a background of spaghetti vacuum of chromomagnetic vortices in QCD. We find a general solution for the zero modes and show that the modes can be localized at pairs of vortices.
The non-local vacuum condensates of QCD describe the distributions of quarks and gluons in the non-perturbative QCD vacuum. Physically, this means that vacuum quarks and gluons have nonzero mean-squared momentum, called virtuality. In this…
We consider the instanton-induced cross section for production of a gluon jet with large transverse momentum in QCD and point out that Mueller's corrections corresponding to the rescattering of hard quanta are likely to remove contributions…
Instantons lead to strong correlations between up and down quarks with spin zero and anti-symmetric color wave functions. In cold and dense matter, $n_b>n_c\simeq 1 fm^{-3}$ and $T<T_c\sim$ 50 MeV, these pairs Bose-condense, replacing the…
We use over-improved stout-link smearing to investigate the presence and nature of instantons on the lattice. We find that smearing can remove short-range effects with little damage to the long-range structure of the gauge field, and that…
We use a matching procedure of sum rules relating the electromagnetic form factors to generalized parton distributions (GPDs) and AdS modes. In this way, in the framework of an AdS/QCD hard-wall model, the helicity-independent GPDs of…
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…
This paper aims to serve as an introductory resource for disseminating the concept of instanton liquid model to individuals with interests in quantum chromodynamics (QCD) for hadrons. We discuss several topological aspects of the QCD vacuum…
The QCD string is manifested through the world-sheet instanton solutions which are responsible for confinement phenomenon and construction of \theta-vacua.
We derive an effective low energy action for QCD in 4 dimensions. The low energy dynamics is described by chiral fields transforming non-trivially under both color and flavor. We use the method of anomaly integration from the QCD action.…
Lattice field theory provides a quantitative tool to study the role of nonperturbative semiclassical configurations in QCD. This talk briefly reviews our present understanding of the role of instantons in QCD and describes in detail new…
It is well known that the instanton approach to QCD generates an effective term which looks like a three flavor determinant of quark bilinears. This has the right behavior to explain the unusual mass and mixing of the $\eta(958)$ meson, as…
We present a simple method to automatically evaluate arbitrary tree-level amplitudes involving the production or decay of a heavy quark pair QQbar in a generic {2S+1}L_J^[1,8] state, i.e., the short distance coefficients appearing in the…
We construct twisted instanton solutions of CP(n) models. Generically a charge-k instanton splits into k(n+1) well-separated and almost static constituents carrying fractional topological charges and being ordered along the noncompact…
Moments of the quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD. Calculations of proton matrix elements of operators corresponding to these moments through the operator product expansion have…
It is shown in a systematic way that the instanton dilute model can be combined with the global colour symmetry model to form a new nonperturbative QCD model. Based on the quark propagator derived in the instanton dilute liquid…
We explore the properties of low lying eigenmodes of fermions in the quenched approximation of lattice QCD. The fermion action is a recently proposed overlap action and has exact chiral symmetry. We find that chiral zero-eigenvalue modes…
In five spacetime dimensions, instantons are finite energy, solitonic particles. We describe the dynamics of these objects in the presence of a Chern-Simons interaction. For U(N) instantons, we show that the 5d Chern-Simons term induces a…
The existing theory of hard exclusive QCD processes is based on two assumptions: (i) $factorization$ into a $hard\,block$ times light front distribution amplitudes (DA's); (ii) use of perturbative gluon exchanges within the hard block.…