Lattice computation of the strange quark mass in QCD

We present a determination of the strange quark mass using lattice QCD. Particular focus is put on the definition and renormalization of the mass. The latter is done non-perturbatively, using a recursive finite-size scaling technique. The hadronic regime of QCD, where the kaon mass is used as input of the calculation, is connected with the perturbative regime, where the strange quark mass can be translated into the MSbar scheme. A summary plot of the present lattice computations using dynamical (sea) quarks is included.Comment: 12 pages, 4 figures, references added, presented at XXIX International Conference of Theoretical Physics, Matter To The Deepest: Recent Developments In Physics of Fundamental Interactions, Ustron, 8-14 September 2005, Polan

Lattice Quantum Chromodynamics

This lecture provides an introduction to quantum chromodynamics (QCD) on the lattice. The continuum limit and Monte Carlo simulations are briefly discussed. Different facets of QCD are nicely exhibited by the potential of a static quark and anti-quark pair and results from lattice calculations of this quantity will be presented.Comment: 17 pages, 5 figures. Proceedings from the Corfu Summer Institute 2016 "School and Workshops on Elementary Particle Physics and Gravity", 31 August - 23 September, 2016, Corfu, Greec

Non-perturbative Gauge-Higgs Unification: Symmetries and Order Parameters

We consider pure SU(N) gauge theories defined on an orbifold lattice, analogous to the S^1/Z_2 gauge theory orbifolds of the continuum, which according to the perturbative analysis do not have a Higgs phase. Non-perturbatively the conclusion for N even is the opposite, namely that spontaneous symmetry breaking does take place and some of the gauge bosons become massive. We interpret this new, non-perturbative phenomenon both mathematically and physically.Comment: 25 pages, 1 figure; figure added and text improve

A new model for confinement

We propose a new approach towards the understanding of confinement. Starting from an anisotropic five dimensional pure gauge theory, we approach a second order phase transition where the system reduces dimensionally. Dimensional reduction is realized via localization of the gauge and scalar degrees of freedom on four dimensional branes. The gauge coupling deriving from the brane Wilson loop observable runs like an asymptotically free coupling at short distance, while it exhibits clear signs of string formation at long distance. The regularization used is the lattice. We take the continuum limit by keeping the ratio of the lattice spacing in the brane over the lattice spacing along the extra dimension constant and smaller than one.Comment: 16 pages, 4 figures; references adde

Non-perturbative mass spectrum of an extra-dimensional orbifold

We analyse non-perturbatively a five-dimensional SU(2) gauge theory compactified on the S^1/Z_2 orbifold. In particular, we present simulation results for the mass spectrum of the theory, which contains a Higgs and a photon. The Higgs mass is found to be free of divergences without fine-tuning. The photon mass is non-zero, thus providing us with the first lattice evidence for a Higgs mechanism derived from an extra dimension. Data from the static potential are consistent with dimensional reduction at low energies.Comment: 4 pages, 3 figure