The title ‘Chiral extrapolations’ of this contribution refers more precisely to chiral extrapolations of lattice QCD data. We shall deal with low-energy aspects of QCD, which are not accessible to ordinary weak-coupling perturbation theory. Possible alternatives to weak-coupling perturbation theory in the low-energy domain of QCD include the investigation of specific models, Monte Carlo simulat...

The current status of theoretical work and experimental analyses on power corrections in QCD for ee annihilation will be reviewed. Measurements of the number of active quark flavours nf and the QCD colour factors CA and CF derived from QCD fits to event shape distributions at lower energies and LEP energies will be presented. The fits are based on O(α2s)+NLLA QCD predictions with power correcti...

The study of QCD processes at the LHC will serve two main goals. First the predictions of QCD will be tested and precision measurements will be performed. Second QCD processes represent a major part of the background to other Standard Model processes and signals of new physics at the LHC and thus need to be understood precisely in the new kinematic region available here. Furthermore, the produc...

It is shown that the quark mass aligns QCD θ vacuum in such a way that the strong CP is conserved, resolving the strong CP problem. Quantum chromodynamics (QCD) is well established as the fundamental theory for the strong interactions. However, there has been a persistent puzzle with QCD, namely the smallness of the strong CP violation. The most general QCD Lagrangian is given in the form:

Recently, a non-Hermitian chiral random matrix model was proposed to describe the eigenvalues of the QCD Dirac operator at nonzero chemical potential. This matrix model can be constructed from QCD by mapping it to an equivalent matrix model which has the same symmetries as QCD with chemical potential. Its microscopic spectral correlations are conjectured to be identical to those of the QCD Dira...

The order parameter of the chiral phase transition is directly related to the infrared part of the spectrum of the QCD Dirac operator. This part of the spectrum follows from the low energy limit of QCD which is given by a partition function of weakly interacting Goldstone modes. We find that the slope of the Dirac spectrum is determined by the pion decay constant whereas for λ ≪ 1/L 2 Λ QCD the...

Results for the first test of the “crude” QCD continuum model, commonly used in QCD Sum Rule analyses, are presented for baryon correlation functions. The QCD continuum model is found to effectively account for excited state contributions to the short-time regime of two-point correlation functions and allows the isolation of ground state properties. Confusion in the literature surrounding the p...

Using the replica method, we analyze the mass dependence of the QCD 3 partition function in a parameter range where the leading contribution is from the zero momentum Goldstone fields. Three complementary approaches are considered in this article. First, we derive exact relations between the QCD 3 partition function and the QCD 4 partition function continued to half-integer topological charge. ...

There are two distinct pictures of the vacuum structure in QCD. One is based on the appearance of color-magnetic monopoles (QCDmonopoles) after performing the abelian gauge xing [1]. The recent lattice QCD simulations show that the dual Meissner e ect brought to the QCD vacuum by QCD-monopole condensation [2]. Hence, color con nement could be regarded as the dual version of the superconductivit...