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Related papers: The Sign Problem via Imaginary Chemical Potential

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We consider a lattice-inspired random matrix model for the QCD chiral phase transition at finite chemical potential. Useful features of the usual RMM for QCD at finite chemical potential are reobtained, some being brought closer to their…

High Energy Physics - Lattice · Physics 2007-05-23 M. A. Halasz

We propose a new method to investigate the thermal properties of QCD with a small quark chemical potential $\mu$. Derivatives of the phase transition point with respect to $\mu$ are computed at $\mu=0$ for 2 flavors of p-4 improved…

High Energy Physics - Lattice · Physics 2008-11-26 C. R. Allton , S. Ejiri , S. J. Hands , O. Kaczmarek , F. Karsch , E. Laermann , Ch. Schmidt , L. Scorzato

We investigate the QCD phase diagram in the strong-coupling lattice QCD with fluctuation and $1/g^2$ effects by using the auxiliary field Monte-Carlo simulations. The complex phase of the Fermion determinant at finite chemical potential is…

High Energy Physics - Lattice · Physics 2015-12-29 Akira Ohnishi , Terukazu Ichihara

The propagator of the domain wall fermion is calculated from the gauge configurations of the RBC-UKQCD collaborations with 2+1 dynamical flavors of $16^3\times 32\times 16$ lattice. The ambiguity of the phase is adjusted such that the…

High Energy Physics - Lattice · Physics 2009-05-20 Sadataka Furui

In [Phys.Rev.Lett.92:162002 (2004), hep-lat/0312025] expressions for the continuous Euclidean time limits of various lattice fermion determinants were derived and compared in order to test universality expectations in Lattice QCD. Here we…

High Energy Physics - Lattice · Physics 2009-11-10 David H. Adams

Using a simple Gaussian-like Ansatz for the phase distribution of a theory with a complex action, we show how the thimble integration for the average phase factor can be plagued by a strong residual sign problem when the phase of the…

High Energy Physics - Lattice · Physics 2018-12-12 Jacques Bloch

The sign problem obstructs the determination of the QCD phase diagram in the temperature-baryon chemical potential plane using lattice QCD. We review the sign problem in QCD and related field theories, including applications to real-time…

High Energy Physics - Lattice · Physics 2026-05-07 Gert Aarts , Dénes Sexty

We simulate lattice QCD with two flavors of Wilson fermions at imaginary baryon chemical potential. Results for the baryon number density computed in the confining and deconfining phases at imaginary baryon chemical potential are used to…

High Energy Physics - Lattice · Physics 2018-08-29 V. G. Bornyakov , D. L. Boyda , V. A. Goy , H. Iida , A. V. Molochkov , Atsushi Nakamura , A. A. Nikolaev , V. I. Zakharov , M. Wakayama

We present a state-of-the-art determination of the complex valued static quark-antiquark potential at phenomenologically relevant temperatures around the deconfinement phase transition. Its values are obtained from non-perturbative lattice…

High Energy Physics - Lattice · Physics 2015-03-05 Yannis Burnier , Olaf Kaczmarek , Alexander Rothkopf

A numerical method is presented for reproducing fermionic quantum gas microscope experiments in equilibrium. By employing nested componentwise direct sampling of fermion pseudo-density matrices, as they arise naturally in determinantal…

Quantum Gases · Physics 2021-08-31 Stephan Humeniuk , Yuan Wan

Wilson Fermions with untwisted and twisted mass are widely used in lattice simulations. Therefore one important question is whether the twist angle and the lattice spacing affect the phase diagram. We briefly report on the study of the…

High Energy Physics - Lattice · Physics 2015-04-17 M. Kieburg , K. Splittorff , J. J. M. Verbaarschot , S. Zafeiropoulos

The fermion-sign problem at finite density is a persisting challenge for Monte-Carlo simulations. Theories that do not have a sign problem can provide valuable guidance and insight for physically more relevant ones that do. Replacing the…

High Energy Physics - Lattice · Physics 2013-01-10 Axel Maas , Lorenz von Smekal , Björn Wellegehausen , Andreas Wipf

Recently, cluster methods have been used to solve a variety of sign problems including those that arise in the presence of fermions. In all cases an analytic partial re-summation over a class of configurations in the path integral was…

High Energy Physics - Lattice · Physics 2009-10-31 Shailesh Chandrasekharan

The method of analytic continuation is one of the most powerful tools to circumvent the sign problem in lattice QCD. The present study is part of a larger project which, based on the investigation of QCD-like theories which are free of the…

High Energy Physics - Lattice · Physics 2010-11-05 P. Cea , L. Cosmai , M. D'Elia , A. Papa

Previously published lattice results for QCD at $\mu_B\neq0$ are compared to analytic predictions for phase quenched QCD. We observe that the strength of the sign problem in QCD is linked directly to the position of the phase transition…

High Energy Physics - Lattice · Physics 2007-05-23 K. Splittorff

In this contribution we investigate the phase diagram of QCD in the presence of an isospin chemical potential. To alleviate the infrared problems of the theory associated with pion condensation, we introduce the pionic source as an infrared…

High Energy Physics - Lattice · Physics 2016-11-22 Bastian B. Brandt , Gergely Endrodi

We utilize the eigenvalue filtering technique combined with the stochastic estimate of the mode number to determine the eigenvalue spectrum. Simulations of (2 + 1)-flavor QCD are performed using the Highly Improved Staggered Quarks…

High Energy Physics - Lattice · Physics 2020-01-16 Heng-Tong Ding , Olaf Kaczmarek , Frithjof Karsch , Sheng-Tai Li , Swagato Mukherjee , Akio Tomiya , Yu Zhang

Using a gap equation for the pion mass a nonperturbative method is given for solving the chiral quark-meson model in the chiral limit at the lowest order in the fermion contributions encountered in a large N_f approximation. The location of…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Jakovac , A. Patkos , Zs. Szep , P. Szepfalusy

We discuss a new Random Matrix Model for QCD with a chemical potential that is based on the symmetries of the Dirac operator and can be solved exactly for all eigenvalue correlations for any number of flavors. In the microscopic limit of…

High Energy Physics - Lattice · Physics 2009-11-10 James C. Osborn

We examine the chiral limit of domain wall fermions in quenched QCD. One expects that in a quenched simulation, exact fermion zero modes will give a divergent, 1/m behavior in the chiral condensate for sufficiently small valence quark…