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[en] Arguments based on recent experimental information are presented to stress the necessity of going beyond the present formulation of Quantum Chromo Dynamics (QCD). A new theory, Anisotropic Chromo-Dynamics (ACD), based on the hadrodynamical pillars: quarks, colour and local symmetry, is discussed and its first successful steps in describing hadrons are outlined
[en] There is by now an ever increasing experimental evidence confirming quantum chromodynamics (QCD). QCD has been particularly successful in predicting, through its asymptotic freedom, the features of high energy and large momentum transfer reactions, like the e/sup +/e/sup -/ annihilation into hadrons, the approximate scale invariance of deep-inelastic lepton-hadron cross sections, the production of the hadronic jets reflecting the elementary quark and gluon subprocesses. Concerning the low energy (large distance) regime there are, on the other hand, the impressive results obtained from the formulation on a space-time lattice, which nicely confirm the expected (non perturbative) confining properties of the theory. Clearly, by extension, we should take QCD as the fundamental theory of nuclear forces, which would open to interesting new nuclear phenomena, outside the traditional range of nuclear physics, directly related to the quarks and gluon degrees of freedom of nuclear matter. This paper is intended to be a short introduction, at a very intuitive level, to the main physical ideas underlying QCD, and to the phenomenological motivations for believing into such a theory
[en] Using existing Monte Carlo data the value of the gluon condensate phi = <0|β(g)/g F sub(μν)sup(2) |0> is estimated. Given the limitations of the method and the available data reasonable agreement is found in both sign and magnitude with the value needed in QCD sum rule calculations. (H.K.)
[en] The symposium included lectures covering both the elements and the experimental tests of the theory of quantum chromdynamics. A three day topical conference was included which included the first results from PETRA as well as the latest reports from CERN, Fermilab, and SPEAR experiments. Twenty-one items from the symposium were prepared separately for the data base
[en] The combined analysis of polarized DIS and SIDIS data is performed in NLO QCD using two alternative procedures: standard fitting procedure and the recently developed direct new method. The results from two methods are compared. The especial attention is paid to the light sea and strange PDFs.
[en] This talk summarizes results for all the scale independent renormalization constants for bilinear currents ( Z A, ZV, and Zs/Zp), the improvement constants (CA, CV, and CT), the quark mass dependence of 20, and the coefficients of the equation of motion operators for O(a) improved lattice QCD. Using data at p = 6.0, 6.2 and 6.4 we study the scaling behavior of these quantities and quantify residual discretization errors.
[en] We discuss the X(5568) particle recently announced by the D0 Collaboration. Several types of models were proposed to explain this structure in the literature. As pointed out by Burns and Swanson (arXiv:1603.04366), none of them provides a satisfactory description of the observation. We provide additional arguments using general properties of QCD, and conclude that the observation of the X(5568), if confirmed, poses serious challenges to our understanding of nonperturbative QCD. (paper)