V. Linke

IS THERE A LANDAU POLE PROBLEM IN QED

We investigate a lattice version of QED by numerical simulations. For the renormalized charge and mass we find results which are consistent with the renormalized charge vanishing in the continuum limit. A detailed study of the relation between bare and renormalized quantities reveals that the Landau pole lies in a region of parameter space which is made inaccessible by spontaneous chiral symmetry breaking.

SEEKING THE EQUATION OF STATE OF NON-COMPACT LATTICE QED

Abstract We perform a high statistics calculation of the equation of state for non-compact QED on large lattices. The calculation extends to fermionic correlation lengths of ≈8, and it is combined with a finite size scaling analysis of the lattice data.

A lattice determination of gA and 〈x〉 from overlap fermions☆

We present results for the nucleon axial charge gA and for the first moment 〈 x 〉 of the unpolarized nucleon structure function from a simulation of quenched overlap fermions.

Resolution of the Landau pole problem in QED

We present new numerical results for the renormalized mass and coupling in non-compact lattice QED with staggered fermions. Implications for the continuum limit and the role of the Landau pole are discussed.

Nucleon Structure from Quenched Overlap Fermions

Theoretical Physics Division, Department of Mathematical Sciences, University of LiverpoolLiverpool L69 3BX, UKE-mail:galletly@ph.ed.ac.uk, martin.guertler@desy.de,rhorsley@ph.ed.ac.uk, karl.koller@lrz.uni-muenchen.de,volkard.linke@physik.fu-berlin.de,rakow@amtp.liv.ac.uk,cjr@amtp.liv.ac.uk, gerrit.schierholz@desy.de,thomas.streuer@desy.deQCDSF CollaborationWe compute the lowest moments of the nucleon’s structure functions using quenched overlapfermions at two different lattice spacings. The renormalisation is done nonperturbatively in theRI

The vacuum polarization: power corrections beyond OPE?

Abstract We compute the vacuum polarization on the lattice using non-perturbatively O(a) improved Wilson fermions. The result is compared with the operator product expansion (OPE).

Mass spectrum and decay constants in the continuum limit

We present first results for light hadron masses, quark masses and decay constants in the continuum limit using O(a) improved fermions at three different values of the gauge coupling β.

Low-lying fermion modes of Nf = 2 improved Wilson fermions

Abstract We present preliminary results for the topological charge and susceptibility determined from the low-lying eigenmodes of the Wilson-Dirac operator. These modes have been computed on dynamical configurations with Nf = 2 non-perturbatively improved Wilson fermions. We compare our results with the eigenmodes of fermions in the quenched approximation.

Improved quenched QCD on large lattices — First results

Continuing our investigations of quenched QCD with improved fermions we have started simulations for lattice size 32^3 x 64 at beta=6.2. We present first results for light hadron masses at kappa=0.13520, 0.13540, and 0.13555. Moreover we compare our initial experiences on the T3E with those for APE/Quadrics systems.

Probing the continuum limit in non-compact QED: New results on large lattices

We present new Monte Carlo results in non-compact lattice QED with staggered fermions down to m 0 = 0.005. This extends our previous investigations on the nature of the continuum limit of QED.