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We construct a model in which four dimensional chiral fermions arise on the boundaries of a five dimensional lattice with free boundary conditions in the fifth direction. The physical content is similar to Kaplan's model of domain wall fermions, yet the present construction has several technical advantages. We discuss some aspects of perturbation theory, as(More)
In this paper we return to a model with domain wall fermions in a waveguide. This model contains a Yukawa coupling y which is needed for gauge invariance. A previous paper left the analysis for large values of this coupling incomplete. We fill the gap by developing a systematic expansion suitable for large y, and using this, we gain an analytic(More)
We develop Chiral Perturbation Theory for chirally broken theories with fermions in two different representations of the gauge group. Any such theory has a non-anomalous singlet U(1)A symmetry, yielding an additional Nambu– Goldstone boson when spontaneously broken. We calculate the next-to-leading order corrections for the pseudoscalar masses and decay(More)
We have carried out a Schrodinger functional (SF) calculation for the SU(3) lattice gauge theory with two flavors of Wilson fermions in the sextet representation of the gauge group. We find that the discrete beta function, which governs the change in the running coupling under a discrete change of spatial scale, changes sign when the SF renormalized(More)
We have measured the running coupling constant of SU(3) gauge theory coupled to N f = 2 flavors of symmetric representation fermions, using the Schrödinger functional scheme. Our lattice action is defined with hypercubic smeared links which, along with the larger lattice sizes, bring us closer to the continuum limit than in our previous study. We observe(More)
We have performed numerical simulations of SU(3) gauge theory coupled to N f = 2 flavors of symmetric representation fermions. The fermions are discretized with the tadpole-improved clover action. Our simulations are done on lattices of length L = 6, 8, and 12. In all simulation volumes we observe a crossover from a strongly coupled confined phase to a weak(More)
We show that the use of the fourth-root trick in lattice QCD with staggered fermions corresponds to a non-local theory at non-zero lattice spacing, but argue that the non-local behavior is likely to go away in the continuum limit. We give examples of this non-local behavior in the free theory, and for the case of a fixed topologically non-trivial background(More)
We apply Schrödinger-functional techniques to the SU(2) lattice gauge theory with N f = 2 flavors of fermions in the adjoint representation. Our use of hypercubic smearing enables us to work at stronger couplings than did previous studies, before encountering a critical point and a bulk phase boundary. Measurement of the running coupling constant gives(More)
We extend our previous study of the SU(3) gauge theory with N f = 2 flavors of fermions in the sextet representation of color. Our tool is the Schrödinger functional method. By changing the lattice action, we push the bulk transition of the lattice theory to stronger couplings and thus reveal the beta function and the mass anomalous dimension γm over a(More)
Consistency of present-day lattice QCD simulations with dynamical (" sea ") staggered fermions requires that the determinant of the staggered-fermion Dirac operator, det(D), be equal to det 4 (D rg) det(T) where D rg is a local one-flavor lattice Dirac operator, and T is a local operator containing only excitations with masses of the order of the cutoff.(More)