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Related papers: Progress on Perfect Lattice Actions for QCD

200 papers

We describe a way to optimize the chiral behavior of Wilson-type lattice fermion actions by studying the low energy real eigenmodes of the Dirac operator. We find a candidate action, the clover action with fat links with a tuned clover…

High Energy Physics - Lattice · Physics 2007-05-23 Thomas DeGrand , Anna Hasenfratz , Tamás G. Kovács

In these lectures I explain how chiral symmetry of continuum QCD naturally leads to a class of lattice regularisations known as twisted mass QCD (tmQCD). As compared to standard Wilson quarks, its advantages are the absence of unphysical…

High Energy Physics - Lattice · Physics 2017-08-23 Stefan Sint

The square root of the positive definite hermitian operator $D_w^{\dagger} D_w$ in Neuberger's proposal of exactly massless quarks on the lattice is implemented by the recursion formula $Y_{k+1} = {1/2} (Y_k + D_w^{\dagger} D_w Y_k^{-1})$…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu

We present a self consistent approach to Coulomb gauge Hamiltonian QCD which allows one to relate single gluon spectral properties to the long range behavior of the confining interaction. Nonperturbative renormalization is discussed. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Adam P. Szczepaniak , Eric S. Swanson

The lattice regularization of QCD provides us with the most systematic way of computing non-perturbative properties of hadrons directly from the first principles of QCD. The recent rapid development of parallel computers has enabled us to…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Kanaya

Large momentum effective field theory provides a new direction for lattice QCD calculations of hadronic structure functions, such as parton distribution functions (PDFs), meson distribution amplitudes, and so on, directly with…

High Energy Physics - Phenomenology · Physics 2018-08-03 Xiaonu Xiong , Thomas Luu , Ulf-G. Meißner

We perform a pilot study of the perturbative renormalization of a Supersymmetric gauge theory with matter fields on the lattice. As a specific example, we consider Supersymmetric ${\cal N}{=}1$ QCD (SQCD). We study the self-energies of all…

High Energy Physics - Lattice · Physics 2017-08-16 M. Costa , H. Panagopoulos

We test a recently proposed improved lattice-fermion action, the fat link clover action, examining indicators of pathological small-quark-mass lattice artifacts ("exceptional configurations") on quenched lattices of spacing 0.12 fm and…

High Energy Physics - Lattice · Physics 2008-11-26 Mark Stephenson , Carleton DeTar , Thomas DeGrand , Anna Hasenfratz

We will discuss here some of the recent results obtained from lattice simulations of QCD at non-zero temperature. Such calculations aim at a quantitative understanding of the thermodynamics of strongly interacting matter in equilibrium. We…

High Energy Physics - Lattice · Physics 2010-11-01 Frithjof Karsch

The overlap Dirac operator, which satisfies the Ginsparg-Wilson relation, realizes exact chiral symmetry on the lattice without any unphysical doubler modes. To perform the path integrals, one should, however, note that the overlap fermion…

High Energy Physics - Lattice · Physics 2007-05-23 Hidenori Fukaya

QCD results are presented for a 2+1 flavour fermion clover action (which we call the SLiNC action). A method of tuning the quark masses to their physical values is discussed. In this method the singlet quark mass is kept fixed, which solves…

QCD is constructed as a lattice gauge theory in which the elements of the link matrices are represented by non-commuting operators acting in a Hilbert space. The resulting quantum link model for QCD is formulated with a fifth Euclidean…

High Energy Physics - Theory · Physics 2016-08-25 R. Brower , S. Chandrasekharan , U. -J. Wiese

A QCD based effective action is constructed to describe the dynamics of confinement and symmetry breaking in the process of parton-hadron conversion. The deconfined quark and gluon degrees of freedom of the perturbative QCD vacuum are…

High Energy Physics - Phenomenology · Physics 2009-10-28 K. Geiger

We calculate the perturbative value of the free energy in QCD on the lattice. This quantity is directly related to the average plaquette. Our calculation is done to 3 loops using the clover action for fermions; the results are presented for…

High Energy Physics - Lattice · Physics 2009-11-10 A. Athenodorou , H. Panagopoulos , A. Tsapalis

The phase diagram of non-compact lattice QED in four dimensions with staggered fermions of charges 1 and $-1/2$ is investigated. The renormalized charges are determined and found to be in agreement with perturbation theory. This is an…

High Energy Physics - Lattice · Physics 2009-10-28 A. Ali Khan

We study lattice QCD in the limit that the quark mass and chemical potential are simultaneously made large, resulting in a controllable density of quarks which do not move. This is similar in spirit to the quenched approximation for zero…

High Energy Physics - Lattice · Physics 2009-10-28 Thomas C. Blum , James E. Hetrick , Doug Toussaint

Quantum Chromodynamics (QCD) is the fundamental theory for the interaction between quarks and gluons. It manifests as the short-range strong interaction inside the nucleus, and plays an important role in the evolution of the early universe,…

High Energy Physics - Lattice · Physics 2013-08-14 Ting-Wai Chiu

I review the lattice formulations of vector-like gauge theories (e.g. QCD) with domain-wall/overlap fermions, and discuss how to optimize the chiral symmetry for any finite $ N_s $ (sites in the fifth dimension). In this formulation, quark…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu

We consider the renormalisation of lattice QCD operators with one and two covariant derivatives related to the first and second moments of generalised parton distributions and meson distribution amplitudes. Employing the clover fermion…

High Energy Physics - Lattice · Physics 2010-10-28 M. Göckeler , R. Horsley , H. Perlt , P. E. L. Rakow , A. Schäfer , G. Schierholz , A. Schiller

Using lattice configurations for quantum chromodynamics (QCD) generated with three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction of QCD's renormalisation-group-invariant process-independent effective…