where sj = dim[Oj ]. In this framework lattice spacing effects can be systematically removed by adding higher dimensional operators to the lattice action. The aim of this work is to design a lattice action such that the coefficients of O(a) and O(a) terms in Eq. (1) can be reduced. For heavy quarks with mQ ≫ ΛQCD, the mass introduces an additional short-distance scale into the problem, and the ...

We performed a calculation of matrix elements of heavy mesons on a quenched lattice, generated with Wilson gauge fields at β = 6.6 with a lattice size of 403 ×80 and a lattice spacing a−1 ≃ 5 GeV determined from the Sommer parameter r0 = 0.5 fm. We use a non-perturbatively O(a) improved Wilson fermion action and improved currents. We have calculated the charmonium spectrum as well as form facto...

A status report is given of the calculations of next-to-leading-order (N = 1) supersymmetric QCD corrections to the production of squarks and gluinos in pp̄/pp collisions. The implementation of these SUSY-QCD corrections leads to more stable theoretical predictions and to a substantial increase of the production cross-sections. In addition we give a discussion of the use of the MS scheme for ren...

The main purpose of this paper is to discuss how firm or steady certain known ball packing are, thinking of them as structures. This is closely related to the property of being locally maximally dense. Among other things we show that many of the usual best-known candidates, for the most dense packings with congruent spherical balls, have the property of being uniformly stable, i.e., for a suffi...

We explore the transitions B(0 +) to B π and Bs(0 +) to B K from lattice QCD with N f = 2 flavours of sea quark, using the static approximation for the heavy quark. We evaluate the effective coupling constants, predicting a B(0 +) to B π width of around 160 MeV. Our result for the coupling strength adds to the evidence that the Bs(0 +) meson is not predominantly a molecular state (BK).

The exact solution of the asymmetric exclusion problem with rstand scond-class particles is presented. In this model the particles (size 1) of both classes are located at lattice points, and di use with equal asymmetric rates, but particles in the rst class do not distinguish those in the second class from holes (empty sites). We generalize and solve exactly this model by considering molecules ...

We discuss some large effects of dynamical fermions. One is a cutoff effect, others concern the contribution of multi-pion states to correlation functions and are expected to survive the continuum limit. We then turn to the preparation for simulations at small lattice spacings which we are planning down to around a = 0.04 fm in order to understand the size of O(a2)-effects of the standard O(a)-...

We develop a topological method of measuring Chern-Simons number change in the real time evolution of classical lattice SU(2) and SU(2) Higgs theory. We find that the ChernSimons number diffusion rate per physical 4-volume is very heavily suppressed in the broken phase, and that it decreases with lattice spacing in pure Yang-Mills theory, although not as quickly as predicted by Arnold, Son, and...

We discuss recent work trying to extract the renormalised quark masses and Λ, the QCD scale, from dynamical simulations in lattice gauge theory.