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Related papers: Complex Langevin Dynamics in 1+1d QCD at Non-Zero …

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In the strong coupling limit, $n$-point functions in lattice QCD with staggered fermions can be rewritten exactly as sums over constrained configurations of monomers, dimers, and baryon loops covering the spacetime lattice. Worm algorithms…

High Energy Physics - Lattice · Physics 2017-02-01 Philippe de Forcrand , Paul Romatschke , Wolfgang Unger , Helvio Vairinhos

We propose a strategy for conducting lattice QCD simulations at fixed volume but variable quark mass so as to investigate the physical effects of dynamical fermions. We present details of techniques which enable this to be carried out…

It is expected that the only effect of heavy dynamical fermions in QCD is to renormalize the gauge coupling. We derive a simple expression for the shift in the gauge coupling induced by $N_f$ flavors of heavy fermions. We compare this…

High Energy Physics - Lattice · Physics 2009-10-22 Anna Hasenfratz , Thomas A. DeGrand

In the complex Langevin approach to lattice simulations at nonzero density, zeroes of the fermion determinant lead to a meromorphic drift and hence a need to revisit the theoretical derivation. We discuss how poles in the drift affect the…

High Energy Physics - Lattice · Physics 2016-11-10 Gert Aarts , Erhard Seiler , Denes Sexty , Ion-Olimpiu Stamatescu

QCD thermodynamics is considered using Wilson fermions in the fixed scale approach. The temperature dependence of the renormalized chiral condensate, quark number susceptibility and Polyakov loop is measured at four lattice spacings…

High Energy Physics - Lattice · Physics 2015-06-05 S. Borsanyi , S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , D. Nogradi , B. C. Toth , N. Trombitas , K. K. Szabo

We analyze the behavior of quarks coupled to a $SU(N_c)$ gauge theory in 1+1 dimensions. In the limit of strong coupling, the model reduces to a Wess-Zumino-Novikov-Witten (WZNW) model. At nonzero density, excitations near the Fermi surface…

High Energy Physics - Theory · Physics 2025-08-18 Marton Lajer , Robert M. Konik , Robert D. Pisarski , Alexei M. Tsvelik

We investigate the deconfining phase transition in SU(3) pure gauge theory and in full QCD with two flavors of staggered fermions by means of a gauge invariant thermal partition functional. In the pure gauge case our finite size scaling…

High Energy Physics - Lattice · Physics 2008-11-26 P. Cea , L. Cosmai , M. D'Elia

We present the results of continuum-extrapolated lattice simulations of quantum chromodynamics (QCD) above the crossover temperature and for unprecedentedly high baryon densities at the physical point, employing the complex Langevin…

High Energy Physics - Lattice · Physics 2026-04-22 Michael Mandl , Dénes Sexty , Daniel Unterhuber

We study the deconfinement transition line in QCD for quark chemical potentials up to $\mu_q \sim 5 T$ ($\mu_B \sim 15 T$). To circumvent the sign problem we use the complex Langevin equation with gauge cooling. The plaquette gauge action…

High Energy Physics - Lattice · Physics 2020-08-05 M. Scherzer , D. Sexty , I. -O. Stamatescu

We apply complex Langevin dynamics to chiral random matrix theory at nonzero chemical potential. At large quark mass the simulations agree with the analytical results while incorrect convergence is found for small quark masses. The region…

High Energy Physics - Lattice · Physics 2013-12-16 A. Mollgaard , K. Splittorff

We use complex Langevin simulations to explore the QCD phase diagram over a large range of chemical potentials and temperatures. For our simulations, we use two flavours of dynamical Wilson fermions with a pion mass of approximately…

High Energy Physics - Lattice · Physics 2021-11-04 Felipe Attanasio , Benjamin Jäger , Felix P. G. Ziegler

We review the existing weak-coupling results on the thermodynamic potential of deconfined QCD at small and large quark chemical potential and compare with results from lattice gauge theory as well as the exactly solvable case of large-N_f…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Gerhold , Andreas Ipp , Anton Rebhan

Lattice 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 temperature and density require anisotropic…

High Energy Physics - Lattice · Physics 2018-11-09 Dennis Bollweg , Marc Klegrewe , Wolfgang Unger

We examine the dynamics of quarks and gauge fields in the lowest energy states in the QED and QCD interactions by combining Schwinger's longitudinal confinement in (1+1)D with Polyakov's transverse confinement in (2+1)D in a ``stretch…

High Energy Physics - Phenomenology · Physics 2023-12-06 Cheuk-Yin Wong , Andrew V. Koshelkin

We explore the compact U(1) lattice gauge theory with staggered fermions and gauge field action -\sum_P [\beta \cos(\Theta_P) + \gamma \cos(2\Theta_P)], both for dynamical fermions and in the quenched approximation. (\Theta_P denotes the…

High Energy Physics - Lattice · Physics 2009-10-30 J. Cox , W. Franzki , J. Jersák , C. B. Lang , T. Neuhaus

Complex Langevin simulations have been able to successfully reproduce results from Monte Carlo methods in the region where the sign problem is mild and make predictions when it is exponentially hard. We present here our study of the QCD…

High Energy Physics - Lattice · Physics 2016-10-25 Gert Aarts , Felipe Attanasio , Benjamin Jäger , Dénes Sexty

We study the effective action for strong-coupling lattice QCD with one-component staggered fermions in the case of nonzero chemical potential and zero temperature. The structure of this action suggests that at large chemical potentials its…

High Energy Physics - Lattice · Physics 2010-02-03 Barak Bringoltz

Kohn and Luttinger showed that a many body system of fermions interacting via short range forces becomes superfluid even if the interaction is repulsive in all partial waves. In gauge theories such as QCD the interaction between fermions is…

High Energy Physics - Phenomenology · Physics 2009-11-11 Thomas Schaefer

We discuss some selected recent developments in the field of lattice QCD at nonzero temperature and density, describing in particular the transition from the hadronic gas to the quark-gluon plasma, as seen in simulations using Wilson…

High Energy Physics - Lattice · Physics 2022-04-13 G. Aarts , C. Allton , S. Hands , B. Jäger , S. Kim , M. P. Lombardo , A. A. Nikolaev , S. M. Ryan , J. -I. Skullerud

We have calculated the pressure and energy density in four-flavour QCD using improved fermion and gauge actions. We observe a strong reduction of finite cut-off effects in the high temperature regime, similar to what has been noted before…

High Energy Physics - Lattice · Physics 2009-10-28 J. Engels , R. Joswig , F. Karsch , E. Laermann , M. Lütgemeier , B. Petersson