Testing imaginary vs. real chemical potential in finite-temperature QCD

Abstract

One suggestion for determining the properties of QCD at finite temperatures and densities is to carry out lattice simulations with an imaginary chemical potential whereby no sign problem arises, and to convert the results to real physical observables only afterwards. We test the practical feasibility of such an approach for a particular class of physical observables, spatial correlation lengths in the quark-gluon plasma phase. Simulations with imaginary chemical potential followed by analytic continuation are compared with simulations with real chemical potential, which are possible by using a dimensionally reduced effective action for hot QCD. We find that for imaginary chemical potential the system undergoes a phase transition at |mu/T| \approx pi/3, and thus observables are analytic only in a limited range. However, utilising this range, relevant information can be obtained for the real chemical potential case.

14 pages. Some clarifications and references added, figures modified. To appear in PLB

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Cited by in corpus (48)

• NJL-model analysis of dense quark matter
• The QCD phase diagram for small densities from imaginary chemical potential
• The QCD thermal phase transition in the presence of a small chemical potential
• Finite density QCD via imaginary chemical potential
• The Equation of State for Two Flavor QCD at Non-zero Chemical Potential
• The QCD Phase Diagram for Three Degenerate Flavors and Small Baryon Density
• The chiral critical line of N_f=2+1 QCD at zero and non-zero baryon density
• The Status of Lattice QCD at Finite Temperature
• QCD thermodynamics from an imaginary mu_B: results on the four flavor lattice model
• Dense Quarks, and the Fermion Sign Problem, in a SU(N) Matrix Model
• The strongly interacting Quark Gluon Plasma, and the critical behaviour of QCD at imaginary chemical potential
• The critical line of two-flavor QCD at finite isospin or baryon densities from imaginary chemical potentials
• Mesonic correlation lengths in high-temperature QCD
• Analytic continuation of the critical line: suggestions for QCD
• Theta dependence of the deconfinement temperature in Yang-Mills theories
• Holographic QCD with Dynamical Flavors
• Lattice QCD at finite temperature and density
• $\theta$ dependence in $SU(3)$ Yang-Mills theory from analytic continuation
• How to get from imaginary to real chemical potential
• Phase diagram of Yang-Mills theories in the presence of a theta term
• Responses of hadrons to chemical potential at finite temperature
• Phase diagram of QCD with four quark flavors at finite temperature and baryon density
• Analytic continuation from imaginary to real chemical potential in two-color QCD
• Real and imaginary chemical potential in 2-color QCD
• Remarks on the multi-parameter reweighting method for the study of lattice QCD at non-zero temperature and density
• The phase diagram of QCD with four degenerate quarks
• Chiral spin symmetry and the QCD phase diagram
• Role of mesonic fluctuations in the Polyakov loop extended quark-meson model at imaginary chemical potential
• Large-$N$ expansion and $\theta$-dependence of $2d$ $C{P}^{N-1}$ models beyond the leading order
• Probing deconfinement in a chiral effective model with Polyakov loop at imaginary chemical potential
• The monopole mass in the three-dimensional Georgi-Glashow model
• Quarks with Twisted Boundary Conditions in the Epsilon Regime
• Strings at Finite Temperature: Wilson Lines, Free Energies, and the Thermal Landscape
• The Roberge-Weiss transition and 't Hooft loops
• The diagonal and off-diagonal quark number susceptibility of high temperature and finite density QCD
• Chiral spin symmetry and hot/dense QCD
• The phase diagram of N_f=3 QCD for small baryon densities
• QCD at high density/temperature
• Framework for non-perturbative analysis of a Z(3)-symmetric effective theory of finite temperature QCD
• QCD phase diagram for small densities from simulations at imaginary mu
• The QCD phase diagram at zero and small baryon density
• Lattice QCD at Finite Temperature and Density
• Finite temperature 2-color QCD for real and imaginary chemical potential
• Classification of sign-problem-free relativistic fermions on the basis of the Majorana positivity
• Exact high temperature expansion of the one-loop thermodynamic potential with complex chemical potential
• QCD phase diagram at small densities from simulations with imaginary mu
• The Fluctuations of the Quark Number and of the Chiral Condensate
• QCD Critical Region and Quark Gluon Plasma from an Imaginary mu_B