The Standard Model of Particle Physics: Status & Low-Energy Tests

Precision measurements of low-energy observables provide stringent tests of the Standard Model structure and accurate determinations of its parameters. An overview of the present experimental status is presented. The main topics discussed are the muon anomalous magnetic moment, the asymptotic freedom of strong interactions, the lepton universality of gauge couplings, the quark flavour structure and CP violation.Comment: 12 pages, 6 Postscript Figure

Electroweak Precision Tests

Precision measurements of electroweak observables provide stringent tests of the Standard Model structure and an accurate determination of its parameters. An overview of the present experimental status is presented.Comment: 11 pages, 9 figures. Invited talk at the International Workshop ``Particles in Astrophysics and Cosmology: from Theory to Observation'' (Valencia, 3-8 May 1999

Logical strength of complexity theory and a formalization of the PCP theorem in bounded arithmetic

We present several known formalizations of theorems from computational complexity in bounded arithmetic and formalize the PCP theorem in the theory PV1 (no formalization of this theorem was known). This includes a formalization of the existence and of some properties of the (n,d,{\lambda})-graphs in PV1

Theoretical status of epsilon'/epsilon

The Standard Model prediction for epsilon'/epsilon is updated, taking into account the most recent theoretical developments. The final numerical value, epsilon'/\epsilon = (17\pm 6) x 10^{-4}, is in good agreement with present measurements.Comment: 6 pages. Invited talk at the 4th Int. Conference on Hyperons, Charm and Beauty Hadrons (Valencia, June 2000

The Standard Model of Electroweak Interactions

What follows is an updated version of the lectures given at the CERN Academic Training (November 1993) and at the Jaca Winter Meeting (February 1994). The aim is to provide a pedagogical introduction to the Standard Model of electroweak interactions. After briefly reviewing the empirical considerations which lead to the construction of the Standard Model Lagrangian, the particle content, structure and symmetries of the theory are discussed. Special emphasis is given to the many phenomenological tests (universality, flavour-changing neutral currents, precision measurements, quark mixing, etc.) which have established this theoretical framework as the Standard Theory of electroweak interactions.Comment: 40 pages, LaTeX (uses cite, epsf), 6 figures (included in a separate uu file). Lectures at the XXII Int. Winter Meeting (Jaca, February, 1994) and at the CERN Academic Training (Geneva, November, 1993

Selected topics on tau physics

The B Factories have generated a large amount of new results on the tau lepton. The present status of some selected topics on tau physics is presented: charged-current universality tests, bounds on lepton-flavour violation, the determination of alpha_s from the inclusive tau hadronic width, and the measurement of |V_{us}| through the Cabibbo-suppressed decays of the tau lepton.Comment: Invited talk at the XXXI International Conference of Theoretical Physics, "Matter to the Deepest", Ustron, Poland, 5-11 September 200