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Overlap Fermion in External Gravity: On a lattice, we construct an overlap Dirac operator which describes the propagation of a Dirac fermion in external gravity. The local Lorentz symmetry is manifestly realized as a lattice gauge symmetry, while the general coordinate invariance is expected to be restored only in the ...
hep-lat
Energies and radial distributions of B_s mesons - the effect of hypercubic blocking: This is a follow-up to our earlier work for the energies and the charge (vector) and matter (scalar) distributions for S-wave states in a heavy-light meson, where the heavy quark is static and the light quark has a mass about that of...
hep-lat
Lattice gauge theory and gluon color-confinement in curved spacetime: The lattice gauge theory for curved spacetime is formulated. A discretized action is derived for both gluon and quark fields which reduces to the generally covariant form in the continuum limit. Using the Wilson action, it is shown analytically that ...
hep-lat
$ππ$ scattering in partially-quenched twisted-mass chiral perturbation theory: We study pion-pion scattering in partially-quenched twisted-mass lattice QCD using chiral perturbation theory. The specific partially-quenched setup corresponds to that used in numerical lattice QCD calculations of the $I=0$ scattering len...
hep-lat
Why the overlap formula does not lead to chiral fermions: We describe a conceptually simple, but important test for the overlap approach to the construction of lattice chiral gauge theories. We explain the equivalence of the overlap formula with a certain waveguide model for a simple set of gauge configurations (the tr...
hep-lat
Naive Lattice Fermion without Doublers: We discuss the naive lattice fermion without the issue of doublers. A local lattice massless fermion action with chiral symmetry and hermiticity cannot avoid the doubling problem from the Nielsen-Ninomiya theorem. Here we adopt the forward finite-difference deforming the $\gamma_...
hep-lat
Topological Susceptibility and Zero Mode Size in Lattice QCD: We use the overlap formalism to define a topological index on the lattice. We study the spectral flow of the hermitian Wilson-Dirac operator and identify zero crossings with topological objects. We determine the topological susceptibility and zero mode size ...
hep-lat
Universality and Scaling at the chiral transition in two-flavor QCD at finite temperature: The order of the phase transition in finite-temperature QCD with two degenerate light quarks is still an open problem and corresponds to the last question mark in the zero-density phase diagram of QCD. We argue that establishin...
hep-lat
The strong-coupling limit of minimal lattice Landau gauge: We study the gluon and ghost propagators of lattice Landau gauge in the strong coupling limit $\beta = 0$ in pure SU(2) lattice gauge theory to find evidence of the conformal infrared behaviour of these propagators as predicted by a variety of functional contin...
hep-lat
Lattice investigation of the phase diagram of the 1+1 dimensional Gross-Neveu model at finite number of fermion flavors: We explore the phase structure of the 1+1 dimensional Gross-Neveu model at finite number of fermion flavors using lattice field theory. Besides a chirally symmetric phase and a homogeneously broken...
hep-lat
Dynamics of Phase Transitions: The 3D 3-state Potts model: In studies of the QCD deconfining phase transition or cross-over by means of heavy ion experiments, one ought to be concerned about non-equilibrium effects due to heating and cooling of the system. In this paper we extend our previous study of Glauber dynamics ...
hep-lat
A Study of Charmonium Systems across the Deconfinement Transition: We present results from lattice studies of charmonium systems near the deconfinement transition temperature. On quenched isotropic lattices with lattice spacings between 0.02 and 0.05 fm, bar{q} q systems with quark masses close to the charm mass and wi...
hep-lat
Two-Dimensional Dynamical Triangulation using the Grand-canonical Ensemble: The string susceptibility exponents of dynamically triangulated two dimensional surfaces with sphere and torus topology were calculated using the grand-canonical Monte Carlo method. We also simulated the model coupled to d-Ising spins (d=1,2,...
hep-lat
Tests of the lattice index theorem: We investigate the lattice index theorem and the localization of the zero-modes for thick classical center vortices. For non-orientable spherical vortices, the index of the overlap Dirac operator differs from the topological charge although the traces of the plaquettes deviate only b...
hep-lat
The Charm Quark on the Lattice: We formulate lattice fermions in a way that encompasses Wilson fermions as well as the static and non-relativistic approximations. In particular, we treat $m_qa$ systematically ($m_q$ is the fermion mass) showing how to understand the Wilson action as an effective action for systems with...
hep-lat
The finite temperature QCD using 2+1 flavors of domain wall fermions at N_t = 8: We study the region of the QCD phase transition using 2+1 flavors of domain wall fermions (DWF) and a $16^3 \times 8$ lattice volume with a fifth dimension of $L_s = 32$. The disconnected light quark chiral susceptibility, quark number s...
hep-lat
Light meson decay constants beyond the quenched approximation: We calculate the effects of including dynamical fermion loops in the lattice QCD estimates of meson decay constants, by extrapolating the results from negative flavour numbers after a suitable matching of the pion and rho mass. For moderately light quarks, ...
hep-lat
Properties of U(1) lattice gauge theory with monopole term: In 4D compact U(1) lattice gauge theory with a monopole term added to the Wilson action we first reveal some properties of a third phase region at negative $\beta$. Then at some larger values of the monopole coupling $\lambda$ by a finite-size analysis we find...
hep-lat
Dirac Spectra of 2-dimensional QCD-like theories: We analyze Dirac spectra of two-dimensional QCD like theories both in the continuum and on the lattice and classify them according to random matrix theories sharing the same global symmetries. The classification is different from QCD in four dimensions because the anti-...
hep-lat
Propagators in lattice Coulomb gauge and confinement mechanisms: We discuss the gluon propagator in 3- and 4-dimensional Yang-Mills theories in Coulomb gauge and compare it with the corresponding Landau gauge propagator, showing that for both the relevant IR mass scale coincides. We also report preliminary results on C...
hep-lat
Simulations of Discrete Random Geometries: Simplicial Quantum Gravity and Quantum String Theory: I investigate two discrete models of random geometries, namely simplicial quantum gravity and quantum string theory. In four-dimensional simplicial quantum gravity, I show that the addition of matter gauge fields to the m...
hep-lat
Employing the perturbative definition of the Higgs mass in a non-perturbative calculation: In perturbative calculations the masses of the Higgs, the Ws and the Z are usually determined from the pole position of the corresponding gauge-dependent propagators. In full non-perturbative lattice calculations it is much mor...
hep-lat
Strange quark contribution to nucleon form factors: We discuss methods for the calculation of disconnected diagrams and their application to various form factors of the nucleon. In particular, we present preliminary results for the strange contribution to the scalar and axial form factors, calculated with N_f=2 dynamic...
hep-lat
Moving NRQCD for B Form Factors at High Recoil: We derive the continuum and lattice tree-level moving NRQCD (mNRQCD) through order 1/m^2. mNRQCD is a generalization of NRQCD for dealing with hadrons with nonzero velocity u_mu. The quark's total momentum is written as P^mu=Mu^mu+k^mu where k^mu << Mu^mu is discretized a...
hep-lat
Worm Algorithm for CP(N-1) Model: The CP(N-1) model in 2D is an interesting toy model for 4D QCD as it possesses confinement, asymptotic freedom and a non-trivial vacuum structure. Due to the lower dimensionality and the absence of fermions, the computational cost for simulating 2D CP(N-1) on the lattice is much lower ...
hep-lat
Non-renormalization theorem in a lattice supersymmetric theory and the cyclic Leibniz rule: N=4 supersymmetric quantum mechanical model is formulated on the lattice. Two supercharges, among four, are exactly conserved with the help of the cyclic Leibniz rule without spoiling the locality. In use of the cohomological ...
hep-lat
Symmetries of mesons after unbreaking of chiral symmetry and their string interpretation: Using the chirally invariant overlap Dirac operator we remove its lowest-lying quasizero modes from the valence quark propagators and study evolution of isovector mesons with J=1. At the truncation level about 50 MeV SU(2)_L \ti...
hep-lat
Can lattice data for two heavy-light mesons be understood in terms of simply two-quark potentials?: By comparing lattice data for the two heavy-light meson system (Q^2 qbar^2) with a standard many-body approach employing only interquark potentials, it is shown that the use of unmodified two-quark potentials leads to ...
hep-lat
Genetic Algorithm for SU(2) Gauge Theory on a 2-dimensional Lattice: An algorithm is proposed for the simulation of pure SU(N) lattice gauge theories based on Genetic Algorithms(GAs). We apply GAs to SU(2) pure gauge theory on a 2 dimensional lattice and show the results, the action per plaquette and Wilson loops, are ...
hep-lat
QCD-like technicolor on the lattice: This talk gives an overview, aimed at non-experts, of the recent progress on the studies of technicolor models on the lattice. Phenomenologically successful technicolor models require walking coupling; thus, an emphasis is put on the determination of the beta-function of various mod...
hep-lat
Screening masses in quenched (2+1)d Yang-Mills theory: universality from dynamics?: We compute the spectrum of gluonic screening-masses in the $0^{++}$ channel of quenched 3d Yang-Mills theory near the phase-transition. Our finite-temperature lattice simulations are performed at scaling region, using state-of-art tec...
hep-lat
The kaon B-parameter from unquenched mixed action lattice QCD: We present a preliminary calculation of B_K using domain-wall valence quarks and 2+1 flavors of improved staggered sea quarks. Both the size of the residual quark mass, which measures the amount of chiral symmetry breaking, and of the mixed meson splitting ...
hep-lat
Meson masses in electromagnetic fields with Wilson fermions: We determine the light meson spectrum in QCD in the presence of background magnetic fields using quenched Wilson fermions. Our continuum extrapolated results indicate a monotonous reduction of the connected neutral pion mass as the magnetic field grows. The v...
hep-lat
Continuum Limit of Scalar Masses and Mixing Energies: We evaluate the continuum limit of the valence approximation to the mass of scalar quarkonium and to the scalar quarkonium-glueball mixing energy for a range of different quark masses. Our results answer several questions raised by the proposed identification of $f_...
hep-lat
Deflated GMRES with Multigrid for Lattice QCD: Lattice QCD solvers encounter critical slowing down for fine lattice spacings and small quark mass. Traditional matrix eigenvalue deflation is one approach to mitigating this problem. However, to improve scaling we study the effects of deflating on the coarse grid in a hie...
hep-lat
Confinement in non-Abelian lattice gauge theory via persistent homology: We investigate the structure of confining and deconfining phases in SU(2) lattice gauge theory via persistent homology, which gives us access to the topology of a hierarchy of combinatorial objects constructed from given data. Specifically, we use...
hep-lat
Anisotropic Improved Gauge Actions; --Perturbative and Numerical Studies --: The $\Lambda$ parameter on the anisotropic lattice, the spatial and temperature coupling constant $g_{\sigma}$, $g_{\tau}$ and their derivative with respaect to the the anisotropy parameter $\xi$ are studied perturbatively for the class of i...
hep-lat
Flavour blindness and patterns of flavour symmetry breaking in lattice simulations of up, down and strange quarks: QCD lattice simulations with 2+1 flavours (when two quark flavours are mass degenerate) typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass and t...
hep-lat
Two-Dimensional Compact N=(2,2) Lattice Super Yang-Mills Theory with Exact Supersymmetry: We construct two-dimensional N=(2,2) lattice super Yang-Mills theory, where the gauge and Higgs fields are all represented by U(N) compact variables, with keeping one exact supercharge along the line of the papers [1,2,3]. Inter...
hep-lat
Lattice calculations of the spectroscopy of baryons with broken flavor SU(3) symmetry and 3, 5, or 7 colors: Lattice Monte Carlo calculations of baryon spectroscopy in gauge groups SU(N), N=3, 5, 7, are presented. The quenched valence fermions come in three flavors, two degenerate mass ones and a third heavier flavor...
hep-lat
Lattice Results for Heavy Light Matrix Elements: Lattice results for heavy light matrix elements are reviewed and some of their implications are very briefly discussed. Despite the fact that in most cases the lattice results for weak matrix elements at the moment have only a modest accuracy of about 20--30\% they alrea...
hep-lat
Infrared Gluon and Ghost Propagators from Lattice QCD. Results from large asymmetric lattices: We report on the infrared limit of the quenched lattice Landau gauge gluon and ghost propagators as well as the strong coupling constant computed from large asymmetric lattices. The infrared lattice propagators are compared...
hep-lat
Two loop lattice expansion of the Schroedinger functional coupling in improved QCD: The contributions of the improved fermion action of Sheikholeslami and Wohlert to the two loop coefficient of the expansion of the Schroedinger functional coupling in terms of the lattice coupling are calculated for the gauge group SU...
hep-lat
Meron-Cluster Simulation of a Chiral Phase Transition with Staggered Fermions: We examine a (3+1)-dimensional model of staggered lattice fermions with a four-fermion interaction and Z(2) chiral symmetry using the Hamiltonian formulation. This model cannot be simulated with standard fermion algorithms because those su...
hep-lat
An Experimenter's View of Lattice QCD: Lattice QCD has the potential this decade to maximize the sensitivity of the entire flavor physics program to new physics and pave the way for understanding physics beyond the Standard Model at the LHC in the coming decade. However, the challenge for the Lattice is to demonstrate ...
hep-lat
Non-Perturbative Renormalization for Staggered Fermions (Self-energy Analysis): We present preliminary results of data analysis for the non-perturbative renormalization (NPR) on the self-energy of the quark propagators calculated using HYP improved staggered fermions on the MILC asqtad lattices. We use the momentum s...
hep-lat
Screening at finite temperature and density: We present lattice QCD results on heavy quark free energies, extract from its temperature dependence entropy and internal energy contributions, and discuss the onset of medium effects that lead to screening of static quark-antiquark sources in a thermal medium. Most results ...
hep-lat
Polymer-Chain Adsorption Transition at a Cylindrical Boundary: In a recent letter, a simple method was proposed to generate solvable models that predict the critical properties of statistical systems in hyperspherical geometries. To that end, it was shown how to reduce a random walk in $D$ dimensions to an anisotropic ...
hep-lat
Hunting the static energy renormalon: We employ Numerical Stochastic Perturbation Theory (NSPT) together with twisted boundary conditions (TBC) to search for the leading renormalon in the perturbative expansion of the static energy. This renormalon is expected to emerge four times faster than the one for the gluon cond...
hep-lat
Form factor ratios for $B_s \rightarrow K \, \ell \, ν$ and $B_s \rightarrow D_s \, \ell \, ν$ semileptonic decays and $|V_{ub}/V_{cb}|$: We present a lattice quantum chromodynamics determination of the ratio of the scalar and vector form factors for two semileptonic decays of the $B_s$ meson: $B_s \rightarrow K \ell...
hep-lat
Behavior near $θ=π$ of the mass gap in the 2D O(3) non-linear sigma model: The validity of the Haldane's conjecture entails that the mass gap of the 2-dimensional O(3) non-linear sigma model with a $\theta$-term must tend to zero as $\theta$ approaches the value $\pi$ by following a precise law. In the present paper ...
hep-lat
Lattice QCD Determination of $g_A$: The nucleon axial coupling, $g_A$, is a fundamental property of protons and neutrons, dictating the strength with which the weak axial current of the Standard Model couples to nucleons, and hence, the lifetime of a free neutron. The prominence of $g_A$ in nuclear physics has made it ...
hep-lat
The QCD Equation of State: Results for the equation of state in 2+1 flavor QCD at zero net baryon density using the Highly Improved Staggered Quark (HISQ) action by the HotQCD collaboration are presented. The strange quark mass was tuned to its physical value and the light (up/down) quark masses fixed to $m_l = 0.05m_s...
hep-lat
The scalar, vector and tensor form factors for the pion and kaon from lattice QCD: We present a calculation of the scalar, vector, and tensor form factors for the pion and kaon in lattice QCD. We use an ensemble of two degenerate light, a strange and a charm quark ($N_f=2+1+1$) of maximally twisted mass fermions with...
hep-lat
Signal/noise enhancement strategies for stochastically estimated correlation functions: We develop strategies for enhancing the signal/noise ratio for stochastically sampled correlation functions. The techniques are general and offer a wide range of applicability. We demonstrate the potential of the approach with a g...
hep-lat
Infinite volume and continuum limits for gluon propagator in 3d SU(2) lattice gauge theory: We study the Landau gauge gluon propagator D(p) in the 3d SU(2) lattice gauge theory. We show that in the infinite-volume limit the expectation values over the Gribov region \Omega, are different (in the infrared) from that ca...
hep-lat
Measure dependence of 2D simplicial quantum gravity: We study pure 2D Euclidean quantum gravity with $R^2$ interaction on spherical lattices, employing Regge's formulation. We attempt to measure the string susceptibility exponent $\gamma_{\rm str}$ by using a finite-size scaling Ansatz in the expectation value of $R^2$...
hep-lat
Lattice Background Effective Action: a Proposal: We propose a method based on the Schr\"odinger functional for computing on the lattice the gauge invariant effective action for external background fields. We check this method by studying the U(1) lattice gauge theory in presence of a constant magnetic background field.
hep-lat
A precise determination of T_c in QCD from scaling: Existing lattice data on the QCD phase transition are analyzed in renormalized perturbation theory. In quenched QCD it is found that T_c scales for lattices with only 3 time slices, and that T_c/Lambda_msbar=1.15 \pm 0.05. A preliminary estimate in QCD with two flavou...
hep-lat
Strange quark momentum fraction from overlap fermion: We present a calculation of $< x >_s$ for the strange quark in the nucleon. We also report the ratio of the strange $< x >$ to that of $u/d$ in the disconnected insertion which will be useful in constraining the global fit of parton distribution functions at small $...
hep-lat
A lattice potential investigation of quark mass and volume dependence of the $Υ$ spectrum: We investigate bottomonia splittings by solving a Schrodinger-Pauli-type equation with parametrisations of QCD potentials around those that have been determined previously in lattice simulations. This is done both, in the conti...
hep-lat
Confinement and Topological Charge in the Abelian Gauge of QCD: We study the relation between instantons and monopoles in the abelian gauge. First, we investigate the monopole in the multi-instanton solution in the continuum Yang-Mills theory using the Polyakov gauge. At a large instanton density, the monopole trajecto...
hep-lat
$1^{-+}$ Hybrid in $J/ψ$ Radiative Decays from Lattice QCD: We present the first theoretical prediction of the production rate of $1^{-+}$ light hybrid meson $\eta_1$ in $J/\psi$ radiative decays. In the $N_f=2$ lattice QCD formalism with the pion mass $m_\pi\approx 350$ MeV, the related electromagnetic multipole form ...
hep-lat
Improved Hamiltonians for Quantum Simulations: Quantum simulations of lattice gauge theories for the foreseeable future will be hampered by limited resources. The historical success of improved lattice actions in classical simulations strongly suggests that Hamiltonians with improved discretization errors will reduce q...
hep-lat
Moving from continuous to discrete symmetry in the 2D XY model: We study the effects of discretization on the U(1) symmetric XY model in two dimensions using the Higher Order Tensor Renormalization Group (HOTRG) approach. Regarding the $Z_N$ symmetric clock models as specific discretizations of the XY model, we compare...
hep-lat
The Quantized $O(1,2)/O(2)\times Z_2$ Sigma Model Has No Continuum Limit in Four Dimensions. II. Lattice Simulation: A lattice formulation of the $O(1,2)/O(2)\times Z_2$ sigma model is developed, based on the continuum theory presented in the preceding paper. Special attention is given to choosing a lattice action (t...
hep-lat
Curvature of the QCD critical line with 2+1 HISQ fermions: We present results on the curvature of the critical line of QCD with 2+1 HISQ fermions at nonzero temperature and quark density obtained by analytic continuation from imaginary chemical potentials. Monte Carlo simulations are performed by means of the MILC code...
hep-lat
A class of chiral fermion models: We study the relation between the Roma and Zaragoza proposals for chiral fermions on the lattice. The fermion action in the Roma approach is shown to be equivalent to one of the Zaragoza type. This result is used to perform a mean-field study of the phase diagram for chiral Yukawa mode...
hep-lat
Scaling in SU(3) Pure Gauge Theory with a Renormalization Group Improved Action: We study the scaling properties of the static quark potential and the ratio of the critical temperature $T_c$ to the square root of the string tension $\sigma$ in the SU(3) pure gauge theory using a renormalization group improved action....
hep-lat
Bound states for Overlap and Fixed Point Actions close to the chiral limit: We study the overlap and the fixed point Dirac operators for massive fermions in the two-flavor lattice Schwinger model. The masses of the triplet (pion) and singlet (eta) bound states are determined down to small fermion masses and the mass ...
hep-lat
The spin structure of the Lambda hyperon in quenched lattice QCD: It has been suggested to use the production of Lambda hyperons for investigating the nucleon spin structure. The viability of this idea depends crucially on the spin structure of the Lambda. Using nonperturbatively O(a) improved Wilson fermions in the qu...
hep-lat
Polyakov loop in 2+1 flavor QCD: We study the temperature dependence of the renormalized Polyakov loop in 2+1 flavor QCD for temperatures T<210 MeV. We extend previous calculations by the HotQCD collaboration using the highly improved staggered quark action and perform a continuum extrapolation of the renormalized Poly...
hep-lat
Implicit schemes for real-time lattice gauge theory: We develop new gauge-covariant implicit numerical schemes for classical real-time lattice gauge theory. A new semi-implicit scheme is used to cure a numerical instability encountered in three-dimensional classical Yang-Mills simulations of heavy-ion collisions by all...
hep-lat
How far can you go ? Surprises and pitfalls in three-flavour chiral extrapolations: The presence of strange sea quark pairs may have a significant impact of the pattern of chiral symmetry breaking : in particular large differences can occur between the chiral limits of two and three massless flavours (i.e., whether $...
hep-lat
The derivative expansion of the renormalization group: By writing the flow equations for the continuum Legendre effective action (a.k.a. Helmholtz free energy) with respect to a particular form of smooth cutoff, and performing a derivative expansion up to some maximum order, a set of differential equations are obtained...
hep-lat
Electromagnetic Corrections in Staggered Chiral Perturbation Theory: To reduce errors in light-quark mass determinations, it is now necessary to consider electromagnetic contributions to light-meson masses. Calculations using staggered quarks and quenched photons are currently underway. Suitably-extended chiral perturb...
hep-lat
Towards continuum limit of screening lengths with chiral Fermions: We investigate mesonic screening correlators at T=2T_c using the overlap Fermions in the quenched approximation, where T_c is the QCD phase transition temperature. Using lattices with temporal extent up to 8, we found that both pseudoscalar and vector c...
hep-lat
The rate of photon production in the quark-gluon plasma from lattice QCD: We calculate the thermal rate of real-photon production in the quark-gluon plasma at a temperature of $T=254$ MeV using lattice QCD. The calculation is based on the difference between the spatially transverse and longitudinal parts of the polariz...
hep-lat
Localised Dirac eigenmodes and Goldstone's theorem at finite temperature: I show that a finite density of near-zero localised Dirac modes can lead to the disappearance of the massless excitations predicted by the finite-temperature version of Goldstone's theorem in the chirally broken phase of a gauge theory.
hep-lat
Vacuum energy of two-dimensional N=(2,2) super Yang-Mills theory: We measure the vacuum energy of two-dimensional N=(2,2) super Yang-Mills theory using lattice simulation. The obtained vacuum energy density is E_0=0.09(9)(+10-8) g^2, where the first error is the systematic and the second is the statistical one, measure...
hep-lat
Machine-learning physics from unphysics: Finding deconfinement temperature in lattice Yang-Mills theories from outside the scaling window: We study the machine learning techniques applied to the lattice gauge theory's critical behavior, particularly to the confinement/deconfinement phase transition in the SU(2) and S...
hep-lat
Energy--momentum tensor on the lattice: recent developments: It is conceivable that the construction of the energy--momentum tensor (EMT) in lattice field theory enlarges our ability in lattice field theory and also deepens our understanding on EMT at the non-pertubative level. In this talk, I will review recent develo...
hep-lat
A Critical Surface of Chiral-invariant System with Gauge Boson and Fermions: In the chirally-invariant context of the $U_{em}(1)$ gauge interaction and four-fermion interactions for ordinary and mirror fermions, the Schwinger-Dyson equation for the fermion self-energy function is studied on a lattice. We find that a ...
hep-lat
End-to-end distribution function for dilute polymers: We study the end-to-end distribution function for dilute polymers. We present a computation to order $O(\epsilon^2)$, $\epsilon = 4 - d$, and discuss in detail its asymptotic behaviour for small and large distances. The theoretical predictions are compared with Mont...
hep-lat
Imaginary chemical potential and finite fermion density on the lattice: Standard lattice fermion algorithms run into the well-known sign problem at real chemical potential. In this paper we investigate the possibility of using imaginary chemical potential, and argue that it has advantages over other methods, particular...
hep-lat
Calculation of Moments of Structure Functions: The progress on the lattice computation of low moments of both the unpolarised and polarised nucleon structure functions is reviewed with particular emphasis on continuum and chiral extrapolations and comparison between quenched and unquenched fermions.
hep-lat
Near-Physical Point Lattice Calculation of Isospin-Breaking Corrections to $K_{\ell2}/π_{\ell2}$: In recent years, lattice determinations of non-perturbative quantities such as $f_K$ and $f_\pi$, which are relevant for $V_{us}$ and $V_{ud}$, have reached an impressive precision of $\mathcal{O}(1\%)$ or better. To mak...
hep-lat
Kaon decays and other hadronic processes in lattice QCD: This thesis deals with the study of properties and interactions of light mesons. Specifically, we focus on hadronic decay and scattering processes, which are dominated by effects of the strong interaction in the low-energy regime. A peculiarity of the strong inte...
hep-lat
A non-perturbative mechanism for elementary particle mass generation: Taking inspiration from lattice QCD data, we argue that a finite non-perturbative contribution to the quark mass is generated as a consequence of the dynamical phenomenon of spontaneous chiral symmetry breaking, in turn triggered by the explicitly br...
hep-lat
Quark chiral condensate from the overlap quark propagator: From the overlap lattice quark propagator calculated in the Landau gauge, we determine the quark chiral condensate by fitting operator product expansion formulas to the lattice data. The quark propagators are computed on domain wall fermion configurations gener...
hep-lat
The QCD phase diagram for small chemical potentials: We compute derivatives of thermodynamic quantities with respect to $\mu$, at $\mu=0$ for 2 and 3 flavors of degenerate quark masses. This allows us to estimate the phase transition line in the $T,\mu$ plane and quantify the influence of a non vanishing chemical poten...
hep-lat
Lattice QCD with Classical and Quantum Electrodynamics: We are doubtlessly familiar with some edition of Jackson's tome on electrodynamics, and Schwinger's calculation of the anomalous magnetic moment of the electron in QED. From the perspective of strong interactions, however, electromagnetic effects usually amount to...
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Hadron Spectrum from Dynamical Lattice QCD Simulations: Recent progress in unquenched lattice QCD simulations is reviewed with emphasis on understanding of chiral behavior for light quark masses.
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Higher representations on the lattice: perturbative studies: We present analytical results to guide numerical simulations with Wilson fermions in higher representations of the colour group. The ratio of $\Lambda$ parameters, the additive renormalization of the fermion mass, and the renormalization of fermion bilinears ...
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A guide to light-cone PDFs from Lattice QCD: an overview of approaches, techniques and results: Within the theory of Quantum Chromodynamics (QCD), the rich structure of hadrons can be quantitatively characterized, among others, using a basis of universal non-perturbative functions: parton distribution functions (PDFs...
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Localized eigenmodes of covariant Laplacians in the Yang-Mills vacuum: As a probe of the Yang-Mills vacuum, we study numerically the eigenmode spectrum of the covariant lattice Laplacian operator. We find that the eigenmodes at the low and high ends of the spectrum are localized in finite regions whose volume is insens...
hep-lat
Extraction of $|V_{cd}|$ and $|V_{cs}|$ from experimental decay rates using lattice QCD $D \to π(K) \ell ν$ form factors: We present a determination of the Cabibbo-Kobayashi-Maskawa matrix elements $|V_{cd}|$ and $|V_{cs}|$ obtained by combining the momentum dependence of the semileptonic vector form factors $f_+^{D ...
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Memory efficient finite volume schemes with twisted boundary conditions: In this paper we explore a finite volume renormalization scheme that combines three main ingredients: a coupling based on the gradient flow, the use of twisted boundary conditions and a particular asymmetric geometry, that for $SU(N)$ gauge theori...
hep-lat
Quenched hadron spectroscopy with improved staggered quark action: We investigate light hadron spectroscopy with an improved quenched staggered quark action. We compare the results obtained with an improved gauge plus an improved quark action, an improved gauge plus standard quark action, and the standard gauge plus st...
hep-lat
Hadron Spectrum in QCD with Valence Wilson Fermions and Dynamical Staggered Fermions at $6/g^2=5.6: We present an analysis of hadronic spectroscopy for Wilson valence quarks with dynamical staggered fermions at lattice coupling $6/g^2 = \beta=5.6$ at sea quark mass $am_q=0.01$ and 0.025, and of Wilson valence quarks ...
hep-lat