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Title: Progress on Complex Langevin simulations of a finite density matrix model for QCD

Abstract

We study the Stephanov model, which is an RMT model for QCD at finite density, using the Complex Langevin algorithm. Naive implementation of the algorithm shows convergence towards the phase quenched or quenched theory rather than to intended theory with dynamical quarks. A detailed analysis of this issue and a potential resolution of the failure of this algorithm are discussed. We study the effect of gauge cooling on the Dirac eigenvalue distribution and time evolution of the norm for various cooling norms, which were specifically designed to remove the pathologies of the complex Langevin evolution. The cooling is further supplemented with a shifted representation for the random matrices. Unfortunately, none of these modifications generate a substantial improvement on the complex Langevin evolution and the final results still do not agree with the analytical predictions.

Authors:
 [1];  [2];  [3];  [4]
  1. Univ. of Regensburg (Germany). Inst. for Theorectical Physics
  2. Swansea Univ., Swansea U.K.
  3. Stony Brook Univ., NY (United States). Dept. of Physics and Astronomy
  4. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); College of William and Mary, Williamsburg, VA (United States); Heidelberg Univ. (Germany). Inst. for Theoretische Physik
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1434244
Report Number(s):
JLAB-THY-18-2693; DOE/OR/23177-4425; arXiv:1801.06456
DOE Contract Number:  
AC05-06OR23177; NSF PHY-1516509
Resource Type:
Conference
Journal Name:
EPJ Web of Conferences
Additional Journal Information:
Journal Volume: 175; Conference: Lattice 2017, 35th International Symposium on Lattice Field Theory, 18-24 Jun 2017. Granada, Spain
Country of Publication:
United States
Language:
English

Citation Formats

Bloch, Jacques, Glesaan, Jonas, Verbaarschot, Jacobus, and Zafeiropoulos, Savvas. Progress on Complex Langevin simulations of a finite density matrix model for QCD. United States: N. p., 2018. Web. doi:10.1051/epjconf/201817507034.
Bloch, Jacques, Glesaan, Jonas, Verbaarschot, Jacobus, & Zafeiropoulos, Savvas. Progress on Complex Langevin simulations of a finite density matrix model for QCD. United States. doi:10.1051/epjconf/201817507034.
Bloch, Jacques, Glesaan, Jonas, Verbaarschot, Jacobus, and Zafeiropoulos, Savvas. Sun . "Progress on Complex Langevin simulations of a finite density matrix model for QCD". United States. doi:10.1051/epjconf/201817507034. https://www.osti.gov/servlets/purl/1434244.
@article{osti_1434244,
title = {Progress on Complex Langevin simulations of a finite density matrix model for QCD},
author = {Bloch, Jacques and Glesaan, Jonas and Verbaarschot, Jacobus and Zafeiropoulos, Savvas},
abstractNote = {We study the Stephanov model, which is an RMT model for QCD at finite density, using the Complex Langevin algorithm. Naive implementation of the algorithm shows convergence towards the phase quenched or quenched theory rather than to intended theory with dynamical quarks. A detailed analysis of this issue and a potential resolution of the failure of this algorithm are discussed. We study the effect of gauge cooling on the Dirac eigenvalue distribution and time evolution of the norm for various cooling norms, which were specifically designed to remove the pathologies of the complex Langevin evolution. The cooling is further supplemented with a shifted representation for the random matrices. Unfortunately, none of these modifications generate a substantial improvement on the complex Langevin evolution and the final results still do not agree with the analytical predictions.},
doi = {10.1051/epjconf/201817507034},
journal = {EPJ Web of Conferences},
number = ,
volume = 175,
place = {United States},
year = {2018},
month = {4}
}

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Works referenced in this record:

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