scholarly journals Investigation of the Thermal QCD Matter from Canonical Sectors

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1273
Author(s):  
Kouji Kashiwa
Keyword(s):  
Quantum Chromodynamics ◽  
Crucial Role ◽  
Phase Structure ◽  
Structural Changes ◽  
Chemical Potential ◽  
Elementary Excitation ◽  
Sharp Change ◽  
Number Density ◽  
Excitation Mode ◽  
Thermal Phase

We discuss the thermal phase structure of quantum chromodynamics (QCD) at zero real chemical potential (μR=0) from the viewpoint of canonical sectors. The canonical sectors take the system to pieces of each elementary excitation mode and thus seem to be useful in the investigation of the confinement–deconfinement nature of QCD. Since the canonical sectors themselves are difficult to compute, we propose a convenient quantity which may determine the structural changes of the canonical sectors. We discuss the quantity qualitatively by adopting lattice QCD prediction for the phase structure with finite imaginary chemical potential. In addition, we numerically estimate this quantity by using the simple QCD effective model. It is shown that there should be a sharp change of the canonical sectors near the Roberge–Weiss endpoint temperature at μR=0. Then, the behavior of the quark number density at finite imaginary chemical potential plays a crucial role in clarifying the thermal QCD properties.

scholarly journals Imaginary Chemical Potential, NJL-Type Model and Confinement–Deconfinement Transition

Symmetry ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 562 ◽  
Author(s):  
Kouji Kashiwa
Keyword(s):  
Phase Diagram ◽  
Finite Temperature ◽  
Crucial Role ◽  
Chemical Potential ◽  
Type Model ◽  
Qcd Phase Diagram

In this review, we present of an overview of several interesting properties of QCD at finite imaginary chemical potential and those applications to exploring the QCD phase diagram. The most important properties of QCD at a finite imaginary chemical potential are the Roberge–Weiss periodicity and the transition. We summarize how these properties play a crucial role in understanding QCD properties at finite temperature and density. This review covers several topics in the investigation of the QCD phase diagram based on the imaginary chemical potential.

scholarly journals SU(3) Polyakov linear-sigma model with finite isospin asymmetry: QCD phase diagram

2019 ◽  
Vol 34 (31) ◽  
pp. 1950199 ◽  
Author(s):  
Abdel Nasser Tawfik ◽  
Abdel Magied Diab ◽  
M. T. Ghoneim ◽  
H. Anwer
Keyword(s):  
Phase Structure ◽  
Sigma Model ◽  
Chemical Potential ◽  
Mean Field ◽  
Field Approximation ◽  
Linear Sigma Model ◽  
Dense Medium ◽  
Mean Field Approximation ◽  
Isospin Asymmetry ◽  
Qcd Phase Diagram

The SU(3) Polyakov linear-sigma model (PLSM) in mean-field approximation is utilized in analyzing the chiral condensates [Formula: see text], [Formula: see text], [Formula: see text] and the deconfinement order parameters [Formula: see text], [Formula: see text], at finite isospin asymmetry. The bulk thermodynamics including pressure density, interaction measure, susceptibility and second-order correlations with baryon, strange and electric charge quantum numbers are studied in thermal and dense medium. The PLSM results are confronted to the available lattice quantum chromodynamics (QCD) calculations. The excellent agreement obtained strengthens the reliability of fixing the PLSM parameters and therefore supports further predictions even beyond the scope of the lattice QCD numerical applicability. From the QCD phase structure at finite isospin chemical potential [Formula: see text], we find that the pseudocritical temperatures decrease with the increase in [Formula: see text]. We conclude that the QCD phase structure in [Formula: see text] plane seems to extend the one in [Formula: see text] plane.

PHASE STRUCTURE OF QED3 AT FINITE CHEMICAL POTENTIAL AND TEMPERATURE

2007 ◽  
Vol 22 (06) ◽  
pp. 449-456 ◽  
Author(s):  
MIN HE ◽  
HONG-TAO FENG ◽  
WEI-MIN SUN ◽  
HONG-SHI ZONG
Keyword(s):  
Phase Diagram ◽  
Wave Function ◽  
Symmetry Breaking ◽  
Quantum Electrodynamics ◽  
Phase Structure ◽  
Chemical Potential ◽  
Chiral Symmetry Breaking ◽  
Three Dimensional ◽  
Mass Function ◽  
Wave Function Renormalization

We study the dynamical chiral symmetry breaking (DCSB) of three-dimensional quantum electrodynamics (QED3) at finite chemical potential and temperature in the framework of Dyson–Schwinger approach. Based on the rainbow approximation and assumption that the wave-function renormalization factor equals to one, the dynamically generated mass function is derived and then the corresponding phase diagram in the (T, μ) plane is obtained.

scholarly journals Equation of State and Freezeout in QCD with Staggered Quarks

2018 ◽  
Vol 175 ◽  
pp. 07035
Author(s):  
Saumen Datta ◽  
R. V. Gavai ◽  
Sourendu Gupta
Keyword(s):  
Equation Of State ◽  
Taylor Expansion ◽  
Chemical Potential ◽  
Baryon Number ◽  
Number Density ◽  
Statistical Errors

We report the equation of state at finite chemical potential, namely the baryon number density and the baryonic contribution to the pressure, using a resummation of the Taylor expansion. We also report the freezeout conditions for a measure of fluctuations. We examine the major sources of systematic and statistical errors in all of these measurements.

scholarly journals Complex Langevin Simulations of QCD at Finite Density – Progress Report

2018 ◽  
Vol 175 ◽  
pp. 07031 ◽  
Author(s):  
D. K. Sinclair ◽  
J. B. Kogut
Keyword(s):  
Importance Sampling ◽  
Langevin Equation ◽  
Phase Structure ◽  
Weak Coupling ◽  
Chemical Potential ◽  
Adaptive Methods ◽  
Progress Report ◽  
Weak Coupling Limit ◽  
Standard Methods ◽  
The Continuum

We simulate lattice QCD at finite quark-number chemical potential to study nuclear matter, using the complex Langevin equation (CLE). The CLE is used because the fermion determinant is complex so that standard methods relying on importance sampling fail. Adaptive methods and gauge-cooling are used to prevent runaway solutions. Even then, the CLE is not guaranteed to give correct results. We are therefore performing extensive testing to determine under what, if any, conditions we can achieve reliable results. Our earlier simulations at β = 6/g2 = 5.6, m = 0.025 on a 124 lattice reproduced the expected phase structure but failed in the details. Our current simulations at β = 5.7 on a 164 lattice fail in similar ways while showing some improvement. We are therefore moving to even weaker couplings to see if the CLE might produce the correct results in the continuum (weak-coupling) limit, or, if it still fails, whether it might reproduce the results of the phase-quenched theory. We also discuss action (and other dynamics) modifications which might improve the performance of the CLE.

MESONS AND DIQUARKS IN A NJL MODEL AT FINITE TEMPERATURE AND CHEMICAL POTENTIAL

1993 ◽  
Vol 08 (07) ◽  
pp. 1295-1312 ◽  
Author(s):  
D. EBERT ◽  
YU. L. KALINOVSKY ◽  
L. MÜNCHOW ◽  
M.K. VOLKOV
Keyword(s):  
Symmetry Breaking ◽  
Chiral Symmetry ◽  
Finite Temperature ◽  
Chemical Potential ◽  
Chiral Symmetry Breaking ◽  
Baryon Number ◽  
Coupling Constants ◽  
Number Density ◽  
Njl Model

An extended NJL model with [Formula: see text] and (qq)-interactions is studied at finite temperature and baryon number density. We investigate the chiral symmetry breaking, its restoration and the behavior of meson and diquark masses, decay and coupling constants as functions of T and µ.

Quantum chromodynamics

2018 ◽  
Author(s):  
Marcos Marino
Keyword(s):  
Symmetry Breaking ◽  
Dirac Operator ◽  
Global Symmetries ◽  
Quantum Chromodynamics ◽  
Random Matrix Theory ◽  
Random Matrix ◽  
Degrees Of Freedom ◽  
Chemical Potential ◽  
Matrix Theory ◽  
Global Symmetry

This article focuses on chiral random matrix theories with the global symmetries of quantum chromodynamics (QCD). In particular, it explains how random matrix theory (RMT) can be applied to the spectra of the Dirac operator both at zero chemical potential, when the Dirac operator is Hermitian, and at non-zero chemical potential, when the Dirac operator is non-Hermitian. Before discussing the spectra of these Dirac operators at non-zero chemical potential, the article considers spontaneous symmetry breaking in RMT and the QCD partition function. It then examines the global symmetries of QCD, taking into account the Dirac operator for a finite chiral basis, as well as the global symmetry breaking pattern and the Goldstone manifold in chiral random matrix theory (chRMT). It also describes the generating function for the Dirac spectrum and applications of chRMT to QCD to gauge degrees of freedom.

scholarly journals ON THERMAL PHASE STRUCTURE OF DEFORMED GROSS–NEVEU MODEL

1996 ◽  
Vol 11 (39n40) ◽  
pp. 3091-3102 ◽  
Author(s):  
H.-T. SATO ◽  
H. TOCHIMURA
Keyword(s):  
Field Theory ◽  
Symmetry Breaking ◽  
Effective Potential ◽  
Phase Structure ◽  
Chiral Symmetry Breaking ◽  
Two Dimensional ◽  
Polymer Model ◽  
Pauli Matrices ◽  
Thermal Phase ◽  
Gross Neveu Model

We illustrate the phase structure of a deformed two-dimensional Gross–Neveu model which is defined by undeformed field contents plus deformed Pauli matrices. This deformation is based on two motives to find a more general polymer model and to estimate how q-deformed field theory affects on its effective potential. Some regions where chiral symmetry breaking and restoration take place repeatedly as temperature increasing are found.

Sign in / Sign up

Export Citation Format

Share Document