[en] The study of classical gauge field theories is considered from the viewpoint of Riemannian geometry. It is seen that such a theory with an n-parameter gauge group is simply general relativity in a (4n+1)-dimensional Riemannian spacetime, Msup(4+n). Classical gauge theories can be based on an equivalence principle generalised to Msup(4+n), in the same way that Einstein gravitation is based on an equivalence principle in M⁴. (A.W.)

[en] The author discusses the application of Monte Carlo methods in QCD. The following topics are covered: lattice QCD; lattice regularisation; the renomalisation group; Wilson loops; the lattice scale; exact numerical results; the Monte Carlo method; string tension; Coulomb law; thermal quark liberation; theories at finite temperature; phase transitions and the critical temperature. The discussion is restricted to pure SU(2) Yang-Mills theory. (A.W.)

[en] The author considers a theory in which the general linear group in four dimensions GL(4,R) and its affine extension GA(4,R) bear a direct relationship to the physics of hadrons, and indirectly to that of leptons. Space-time properties of leptons and hadrons are studied. GA(4,R) is postulated as a local gauge theory. This group translates and deforms the tetrads of the locally Minkowskian space-time. Its conserved currents, energy-momentum and hypermomentum, act as sources in the two field equations of gravity. The irreducible pieces of the torsion and curvature tensor operators are found, as well as their Lorentz and and spin content. A Lagrangian quadratic in torsion and curvature is chosen. In the large scale region it generates an Einstein-like gravitational interaction, and possibly prevents development of singularities. In the particle physics domain it yields a renormalizable gauge field theory. In the linear approximation, for a static source, one finds a confinement potential which applies only to the hadronic matter. (A.W.)

[en] A discussion is given of the gauge nature of the Lagrangian for electro-weak interactions. Of particular importance is a test of the vector field self-interaction. This may be provided by the decay Z→W⁺l^-anti γsub(l). As a preliminary to this test, a computation is given of the decay Z→W⁺π^-. A very small branching fraction is predicted, of order (0.5-0.6)x10^-7 GeV. (A.W.)

[en] A review is given of ideas about magnetic monopoles. Attention is drawn to the still unexplained observations of Schein, Haskin and Glasser (1954), in which electron-positron pairs were produced in large numbers by a cosmic-ray interaction. Their experiment has been simulated in 300 GeV pN interactions at Fermilab, giving a production limit of 10^-7 per proton interaction. The explanation for this phenomenon may lie in magnetic monopoles, or it may be similar to that invoked to explain the so-called Centauro events. (A.W.)

[en] The author reviews possible tests of flavour symmetry breaking ('penguinology') in QCD, including angular asymmetry of photons in the process np→dγ, CP violation in the K⁰-anti K⁰ system, B meson decays. A fuller discussion is given of D meson decays, where the standard model does not give good agreement with experiment. (A.W.)

[en] The author considers nonAbelian gauge theories built on a classical level, concentrating on the group SU(2). Features of this theory are outlined, contrasting them with features of electrodynamics. The static solutions of R. Jackiw et al. (1979) are also considered. Candidates for physical quantities are discussed following previous work by the author. (A.W.)

[en] Lecture notes are given on the subject of unified field theories. The discussion covers the SU(2)x U(1) electroweak model, applications of elementary scalar fields, unification beyond U(1)xSU(2)xSU(3) and grand unified theories based on SU(5) or SO(10). (A.W.)

[en] Some general considerations are given on quark confinement, defining, for instance, the Wilson loop criterion for confinement and its applicability. The argument of 't Hooft for what phases are possible for QCD, is reviewed. Various approaches to decide the actually realized phase are mentioned briefly. One approach, based on the suggestion that the vacuum is color ferromagnetic in QCD, is treated in some detail. This idea leads in succession to a series of pictures of the QCD vacuum. A constant magnetic field state is unstable, so that it cannot be the true ground state. This observation gave rise to further developments into the ideas of the vacuum called the Copenhagen vacuum. Special emphasis is put on estimating the MIT bag constant on arguing for a liquid nature of the flux tubes and for confinement. The vacuum ideas have been used to make a set of predictions for the hadron spectrum. Briefly mentioned are works on the inseparability of the confinement and Higgs phases. (A.W.)

[en] The author discusses critical phenomena in a system of strongly interacting particles, which occur as the density of such particles is progressively increased. The discussion centres around three approaches to this phenomenon: the statistical approach; quark bag models; quantum chromodynamics. (A.W.)