163 citations · 1k across the 20 of their papers we have counts for
20 papers
Non-Perturbative Improvement of the Anisotropic Wilson QCD Action
T. R. Klassen
We describe the first steps in the extension of the Symanzik O() improvement program for Wilson-type quark actions to anisotropic lattices, with a temporal lattice spacing small…
The Anisotropic Wilson Gauge Action
T. R. Klassen
Anisotropic lattices, with a temporal lattice spacing smaller than the spatial one, allow precision Monte Carlo calculations of problems that are difficult to study otherwise: heav…
A quark action for very coarse lattices
M. Alford, Timothy Klassen, Peter Lepage
We investigate a tree-level O(a^3)-accurate action, D234c, on coarse lattices. For the improvement terms we use tadpole-improved coefficients, with the tadpole contribution measure…
The Effectiveness of Non-Perturbative O(a) Improvement in Lattice QCD
R. G. Edwards, U. M. Heller, T. R. Klassen
The ALPHA collaboration has determined the O(a) improved Wilson quark action for lattice spacings fm, in the quenched approximation. We extend this result to coarser la…
Accurate Scale Determinations for the Wilson Gauge Action
R. G. Edwards, U. M. Heller, T. R. Klassen
Accurate determinations of the physical scale of a lattice action are required to check scaling and take the continuum limit. We present a high statistics study of the static poten…
The Schrödinger Functional and Non-Perturbative Improvement
R. G. Edwards, U. M. Heller, T. R. Klassen
After describing the Schrödinger functional for standard and improved gluon and quark actions we present results for the non-perturbative clover coefficients of the SW quark action…
Mean-link tadpole improvement of SW and D234 actions
Mark Alford, Timothy R. Klassen, Peter Lepage
We investigate a tadpole-improved tree-level-O(a^3)-accurate action, D234c, on coarse lattices, using the mean link in Landau gauge to measure the tadpole contribution. We find tha…
The Schrödinger Functional for Improved Gluon and Quark Actions
T. R. Klassen
The Schrödinger Functional (quantum/lattice field theory with Dirichlet boundary conditions) is a powerful tool in the non-perturbative improvement and for the study of other aspec…
Improved Quark Actions for Lattice QCD
T. R. Klassen
I present a brief summary of the status and prospects of improved Wilson-type quark actions for coarse lattice simulations. My conclusions are optimistic.
Improving Lattice Quark Actions
M. Alford, T. R. Klassen, G. P. Lepage
We explore the first stage of the Symanzik improvement program for lattice Dirac fermions, namely the construction of doubler-free, highly improved classical actions on isotropic a…
Towards Highly Improved Quark Actions
M. G. Alford, T. R. Klassen, G. P. Lepage
We describe two ideas useful in the construction of highly improved quark actions for simulations on coarse lattices: (1) Field transformations to solve the doubler problem without…
The D234 action for light quarks
M. Alford, T. Klassen, P. Lepage
We investigate a new light fermion action (the ``D234'' action), which is accurate up to and tadpole-improved errors. Using D234 with Symanzik- and tadpole-impr…
How to Accurately Extract the Running Coupling of QCD from Lattice Potential Data
Timothy R. Klassen
By (a) using an expression for the LATTICE potential of QCD in terms of a CONTINUUM running coupling and (b) globally parameterizing this coupling to interpolate between 2- (or hig…
The (LATTICE) QCD Potential and Running Coupling: How to Accurately Interpolate between Multi-Loop QCD and the String Picture
Timothy R. Klassen
We present a simple parameterization of a running coupling constant, defined via the static potential, that interpolates between 2-loop QCD in the UV and the string prediction in t…
Quasi-Particles, Conformal Field Theory, and -Series
S. Dasmahapatra, R. Kedem, T. R. Klassen +2
We review recent results concerning the representation of conformal field theory characters in terms of fermionic quasi-particle excitations, and describe in detail their construct…
Fermionic Sum Representations for Conformal Field Theory Characters
R. Kedem, T. R. Klassen, B. M. McCoy +1
We present sum representations for all characters of the unitary Virasoro minimal models. They can be viewed as fermionic companions of the Rocha-Caridi sum representations, the la…
Fermionic Quasi-Particle Representations for Characters of
R. Kedem, T. R. Klassen, B. M. McCoy +1
We present fermionic quasi-particle sum representations for some of the characters (or branching functions) of ~ ~for all simply-lace…
Sine-Gordon =/= Massive Thirring, and Related Heresies
Timothy R. Klassen, Ezer Melzer
By viewing the Sine-Gordon and massive Thirring models as perturbed conformal field theories one sees that they are different (the difference being observable, for instance, in fin…
Kinks in Finite Volume
Timothy R. Klassen, Ezer Melzer
A (1+1)-dimensional quantum field theory with a degenerate vacuum (in infinite volume) can contain particles, known as kinks, which interpolate between different vacua and have non…
Rg Flows in the -Series of Minimal Cfts
Timothy R. Klassen, Ezer Melzer
Using results of the thermodynamic Bethe Ansatz approach and conformal perturbation theory we argue that the -perturbation of a unitary minimal -dimensional conform…