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Title: Complex Langevin simulation of a random matrix model at nonzero chemical potential

Journal Article · · Journal of High Energy Physics (Online)
 [1];  [2];  [3];  [4]
  1. Univ. of Regensburg, Regensburg (Germany)
  2. Swansea Univ., Swansea (United Kingdom)
  3. Stony Brook Univ., Stony Brook, NY (United States)
  4. Heidelberg Univ., Heidelberg (Germany); The College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

In this study we test the complex Langevin algorithm for numerical simulations of a random matrix model of QCD with a first order phase transition to a phase of finite baryon density. We observe that a naive implementation of the algorithm leads to phase quenched results, which were also derived analytically in this article. We test several fixes for the convergence issues of the algorithm, in particular the method of gauge cooling, the shifted representation, the deformation technique and reweighted complex Langevin, but only the latter method reproduces the correct analytical results in the region where the quark mass is inside the domain of the eigenvalues. In order to shed more light on the issues of the methods we also apply them to a similar random matrix model with a milder sign problem and no phase transition, and in that case gauge cooling solves the convergence problems as was shown before in the literature.

Research Organization:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Nuclear Physics (NP)
Grant/Contract Number:
AC05-06OR23177; NSF PHY-1516509
OSTI ID:
1434242
Report Number(s):
JLAB-THY-18-2691; DOE/OR/23177-4423; arXiv:1712.07514; PII: 7727; TRN: US1802554
Journal Information:
Journal of High Energy Physics (Online), Vol. 2018, Issue 3; ISSN 1029-8479
Publisher:
Springer BerlinCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 21 works
Citation information provided by
Web of Science

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Cited By (6)

Review on novel methods for lattice gauge theories journal January 2020
Dynamical stabilisation of complex Langevin simulations of QCD journal January 2019
Complex Langevin simulations of zero-dimensional supersymmetric quantum field theories journal October 2019
Polarized fermions in one dimension: density and polarization from complex Langevin calculations, perturbation theory, and the virial expansion text January 2018
Complex Langevin and boundary terms text January 2018
Review on novel methods for lattice gauge theories text January 2019

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