Non perturbative physics from NSPT: renormalons, the gluon condensate and all thatNumerical Stochastic Perturbation Theory (NSPT) enables very high order computations in Lattice Gauge Theories. We report on the determination of the gluon condensate from lattice QCD measurements of…Luigi Del Debbio, Francesco Di Renzo, Gianluca Filaci·Nov 13, 2018SaveLearn
Comparison between models of QCD with and without dynamical charm quarksWe investigate the influence of dynamical charm quarks on observables that depend explicitly on the charm quark fields, like the pseudo-scalar and vector masses mηc and mJ/ψ, the hyperfine…Salvatore Cali, Francesco Knechtli, Tomasz Korzec·Nov 13, 2018SaveLearn
Gaussian states for the variational study of (1+1)-dimensional lattice gauge modelsWe introduce a variational ansatz based on Gaussian states for (1+1)-dimensional lattice gauge models. To this end we identify a set of unitary transformations which decouple the gauge degrees of…P. Sala, T. Shi, S. Kühn et al.·Nov 12, 2018SaveLearn
On the Critical Flavor Number in the 2+1d Thirring ModelThe Thirring model in 2+1 spacetime dimensions, in which N flavors of relativistic fermion interact via a contact interaction between conserved fermion currents, is studied using lattice field…Simon Hands·Nov 12, 2018SaveLearn
Localisation, chiral symmetry and confinement in QCD and related theoriesI discuss recent results on the relation between the localisation of low-lying Dirac eigenmodes, the restoration of chiral symmetry, and deconfinement in QCD and QCD-like models, providing evidence…Matteo Giordano·Nov 12, 2018SaveLearn
Is SU(3) gauge theory with 13 massless flavors conformal?We use lattice simulations to study SU(3) gauge theory with 13 massless fermions in the fundamental representation. We present evidence that the theory is conformal with a non-zero infrared fixed…Zoltan Fodor, Kieran Holland, Julius Kuti et al.·Nov 12, 2018SaveLearn
bbud tetraquark resonances in the Born-Oppenheimer approximation using lattice QCD potentialsWe study tetraquark resonances using lattice QCD potentials for a pair of static antiquarks bb in the presence of two light quarks ud. The system is treated in the Born-Oppenheimer…Martin Pflaumer, Pedro Bicudo, Marco Cardoso et al.·Nov 12, 2018SaveLearn
Equation of state near the first order phase transition point of SU(3) gauge theory using gradient flowWe study energy gap (latent heat) between the hot and cold phases at the first order phase transition point of the SU(3) gauge theory. Performing simulations on lattices with various spatial volumes…Mizuki Shirogane, Shinji Ejiri, Ryo Iwami et al.·Nov 10, 2018SaveLearn
Determination of the quark condensate from heavy-light current-current correlators in full lattice QCDWe derive the Operator Product Expansion whose vacuum expectation value gives the time-moments of the pseudoscalar heavy-light current-current correlator up to and including terms in αs2…C. T. H. Davies, K. Hornbostel, J. Komijani et al.·Nov 10, 2018SaveLearn
Identifying spin and parity of charmonia in flight with lattice QCDThe spectrum of charmonium resonances contains a number of unanticipated states along with several conventional quark-model excitations. The hadrons of different quantum numbers JP appear in a…M. Padmanath, Sara Collins, Daniel Mohler et al.·Nov 9, 2018SaveLearn
Indications for infrared conformal behaviour of SU(2) gauge theory with Nf = 3/2 flavours of adjoint fermionsWe present the results of a numerical investigation of SU(2) gauge theory with Nf=3/2 flavours of fermions, corresponding to 3 Majorana fermions, which transform in the adjoint representation of…Georg Bergner, Pietro Giudice, Istvan Montvay et al.·Nov 9, 2018SaveLearn
Progress on the nature of the QCD thermal transition as a function of quark flavors and massesWe investigate to which extent we can exploit the dependence of the order of the chiral transition on the number of light degenerate flavors Nf, re-interpreted as continuous parameter in…Francesca Cuteri, Owe Philipsen, Alessandro Sciarra·Nov 9, 2018SaveLearn
Towards Lefschetz thimbles regularization of heavy-dense QCDAt finite density, lattice simulations are hindered by the well-known sign problem: for finite chemical potentials, the QCD action becomes complex and the Boltzmann weight e-S cannot be…Kevin Zambello, Francesco Di Renzo·Nov 8, 2018SaveLearn
Reducing Autocorrelation Times in Lattice Simulations with Generative Adversarial NetworksShort autocorrelation times are essential for a reliable error assessment in Monte Carlo simulations of lattice systems. In many interesting scenarios, the decay of autocorrelations in the Markov…Jan M. Pawlowski, Julian M. Urban·Nov 8, 2018SaveLearn
Exploratory study of the off-shell properties of the weak vector bosonsGauge invariance requires even in the weak interactions that physical, observable particles are described by gauge-invariant composite operators. Such operators have the same structure as those…Axel Maas, Sebastian Raubitzek, Pascal Törek·Nov 8, 2018SaveLearn
A new method for suppressing excited-state contaminations on the nucleon form factorsOne of the most challenging tasks in lattice calculations of baryon form factors is the analysis and control of excited-state contaminations. Taking the isovector axial form factors of the nucleon as…Harvey B. Meyer, Konstantin Ottnad, Tobias Schulz·Nov 8, 2018SaveLearn
Implementation of the conjugate gradient algorithm on FPGA devicesResults of porting parts of the Lattice Quantum Chromodynamics code to modern FPGA devices are presented. A single-node, double precision implementation of the Conjugate Gradient algorithm is used to…Piotr Korcyl, Grzegorz Korcyl·Nov 8, 2018SaveLearn
Thermodynamics at Strong Coupling on Anisotropic LatticesLattice QCD with staggered fermions at strong coupling has long been studied in a dual representation to circumvent the finite baryon density sign problem. Monte Carlo simulations at finite…Dennis Bollweg, Marc Klegrewe, Wolfgang Unger·Nov 8, 2018SaveLearn
J/ψ -nucleon scattering in Pc+ pentaquarks channelTwo pentaquarks Pc+ were discovered by LHCb collaboration as peaks in the proton-J/ψ invariant mass. We perform the lattice QCD study of the scattering between J/ψ meson and nucleon in…Ursa Skerbis, Sasa Prelovsek·Nov 8, 2018SaveLearn
Perturbative investigation of Wilson-line operators in Parton PhysicsWe investigate the renormalization of a class of gauge-invariant nonlocal quark bilinear operators, including a finite-length Wilson-line (called Wilson-line operators). The matrix elements of these…Gregoris Spanoudes, Haralambos Panagopoulos·Nov 8, 2018SaveLearn
Unwrapping phase fluctuations in one dimensionCorrelation functions in one-dimensional complex scalar field theory provide a toy model for phase fluctuations, sign problems, and signal-to-noise problems in lattice field theory. Phase unwrapping…William Detmold, Gurtej Kanwar, Michael L. Wagman·Nov 7, 2018SaveLearn
Renormalization Group Properties of Scalar Field Theory Using Gradient FlowGradient flow has proved useful in the definition and measurement of renormalized quantities on the lattice. Recently, the fact that it suppresses high-modes of the field has been used to construct…Andrea Carosso, Anna Hasenfratz, Ethan T. Neil·Nov 7, 2018SaveLearn
A Lattice Study of Renormalons in Asymptotically Free Sigma ModelsIn general, perturbative expansions of observables in powers of the coupling constant in quantum field theories are asymptotic series. In many cases it is possible to apply resummation techniques to…Matthias Puhr, Falk Bruckmann·Nov 7, 2018SaveLearn
Towards a Dual Representation of Lattice QCDOur knowledge about the QCD phase diagram at finite baryon chemical potential μB is limited by the well known sign problem. The path integral measure, in the standard determinantal approach,…Giuseppe Gagliardi, Wolfgang Unger·Nov 7, 2018SaveLearn
Thermodynamics for SU(2) pure gauge theory using gradient flowWe present the scale-setting function and the equation of state of the pure SU(2) gauge theory using the gradient flow method. We propose a reference scale t0 for the SU(2) gauge theory satisfying…Takehiro Hirakida, Etsuko Itou, Hiroaki Kouno·Nov 7, 2018SaveLearn