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Related papers: Complex Langevin: Boundary terms and application t…

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We demonstrate that the complex Langevin method (CLM) enables calculations in QCD at finite density in a parameter regime in which conventional methods, such as the density of states method and the Taylor expansion method, are not…

High Energy Physics - Lattice · Physics 2020-12-02 Yuta Ito , Hideo Matsufuru , Yusuke Namekawa , Jun Nishimura , Shinji Shimasaki , Asato Tsuchiya , Shoichiro Tsutsui

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

The complex Langevin method is a leading candidate for solving the sign problem occurring in various physical situations, notably QCD at finite chemical potential. Its most vexing problem is `convergence to the wrong limit', where the…

High Energy Physics - Lattice · Physics 2011-10-27 Gert Aarts , Frank A. James , Erhard Seiler , Ion-Olimpiu Stamatescu

We propose a novel quasiparticle interpretation of the equation of state of deconfined QCD at finite temperature. Using appropriate thermal masses, we introduce a phenomenological parametrisation of the onset of confinement in the vicinity…

High Energy Physics - Phenomenology · Physics 2009-11-07 R. A. Schneider , T. Renk , M. Thaler , A. Polleri , W. Weise

Finite temperature lattice QCD is probed by varying the temporal boundary conditions of the fermions. We develop the emerging physical behavior in a study of the quenched case and subsequently present first results for a fully dynamical…

High Energy Physics - Lattice · Physics 2010-04-30 Erek Bilgici , Falk Bruckmann , Julia Danzer , Christof Gattringer , Christian Hagen , Ernst Michael Ilgenfritz , Axel Maas

We carry out a finite density calculation based on a canonical approach which is designed to address the overlap problem. Two degenerate flavor simulations are performed using Wilson gauge action and Wilson fermions on $4^4$ lattices, at…

High Energy Physics - Lattice · Physics 2016-08-16 Andrei Alexandru , Manfried Faber , Ivan Horváth , Keh-Fei Liu

We study complex Langevin simulations of a toy model as well as QCD, supplemented with a dynamical stabilization (DS) term, which was proposed to regularize the complexified process at lower temperatures. We compare the results to…

High Energy Physics - Lattice · Physics 2024-06-03 Michael W. Hansen , Dénes Sexty

We study an effective theory for QCD at finite temperature and density which contains the leading center symmetric and center symmetry breaking terms. The effective theory is studied in a flux representation where the complex phase problem…

High Energy Physics - Lattice · Physics 2011-07-21 Ydalia Delgado Mercado , Hans Gerd Evertz , Christof Gattringer

Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with…

High Energy Physics - Lattice · Physics 2016-08-24 Keitaro Nagata , Jun Nishimura , Shinji Shimasaki

We give an update on our current project to determine the transition temperature and the order of the deconfinement transition in the chiral limit of two flavour QCD. We use nonperturbatively O(a) improved Wilson fermions of the…

High Energy Physics - Lattice · Physics 2011-08-17 Bastian B. Brandt , Owe Philipsen , Hartmut Wittig , Lars Zeidlewicz

The critical temperature and the nature of the QCD finite temperature phase transition are determined for Nf=2 dynamical flavors of nonperturbatively improved Wilson fermions. The calculations are performed on large lattices with temporal…

High Energy Physics - Lattice · Physics 2014-11-20 V. G. Bornyakov , R. Horsley , S. M. Morozov , Y. Nakamura , M. I. Polikarpov , P. E. L. Rakow , G. Schierholz , T. Suzuki

We calculate the QCD cross-over temperature, the equation of state and fluctuations of conserved charges at finite density by analytical continuation from imaginary to real chemical potentials. Our calculations are based on new continuum…

Nuclear Theory · Physics 2016-11-23 R. Bellwied , S. Borsanyi , Z. Fodor , J. Gunther , S. D. Katz , A. Pasztor , C. Ratti , K. K. Szabo

The sign problem appears in lattice QCD as soon as a non-zero chemical potential is introduced. This prevents direct simulations to determine the phase structure of the strongly interacting matter. Complex Langevin methods have been…

High Energy Physics - Lattice · Physics 2018-04-18 Felipe Attanasio , Benjamin Jäger

We study lattice QCD at non-vanishing chemical potential using the complex Langevin equation. We compare the results with multi-parameter reweighting both from $\mu=0$ and phase quenched ensembles. We find a good agreement for lattice…

High Energy Physics - Lattice · Physics 2015-12-02 Z. Fodor , S. D. Katz , D. Sexty , C. Török

For QCD with Wilson fermions at isospin chemical potential we study the finite phase transition on an $8^3\times4$ lattice at $\kappa=0.15$. We use two gauge actions: Wilson action and DBW2 action. Both actions give the same results. The…

High Energy Physics - Lattice · Physics 2009-11-10 A. Nakamura , T. Takaishi

Monte Carlo studies of QCD at finite density suffer from the sign problem, which becomes easily uncontrollable as the chemical potential $\mu$ is increased even for a moderate lattice size. In this work we make an attempt to approach the…

High Energy Physics - Lattice · Physics 2018-12-06 Yuta Ito , Hideo Matsufuru , Jun Nishimura , Shinji Shimasaki , Asato Tsuchiya , Shoichiro Tsutsui

We investigate the applicability of complex Langevin dynamics to the three-dimensional XY model at finite chemical potential. To assess correctness, we introduce a new diagnostic based on the configurational temperature (or configurational…

High Energy Physics - Lattice · Physics 2025-09-17 Anosh Joseph , Arpith Kumar

Machine learning is applied to investigate the phase transition of two-dimensional complex plasmas. The Langevin dynamics simulation is employed to prepare particle suspensions in various thermodynamic states. Based on the resulted particle…

Plasma Physics · Physics 2023-07-25 He Huang , Vladimir Nosenko , Han-Xiao Huang-Fu , Hubertus M. Thomas , Cheng-Ran Du

The complex Langevin approach is a promising method for the numerical treatment of systems with a sign problem, for which conventional lattice field theory techniques based on importance sampling cannot be applied. However, complex Langevin…

High Energy Physics - Lattice · Physics 2026-04-15 Michael Mandl

Applying the "Complexity=Action" conjecture, we study the holographic complexity close to crossover/phase transition in a holographic QCD model proposed by Gubser et al. This model can realize three types of phase transition, crossover or…

High Energy Physics - Theory · Physics 2018-02-27 Shao-Jun Zhang