scholarly journals Effective Potential Formalism at Finite Temperature in Dual QCD and Deconfilnement Phase Transition

2019 ◽  
Vol 201 ◽  
pp. 09009
Author(s):  
Garima Punetha ◽  
H. C. Chandola
Keyword(s):  
Phase Transition ◽  
Thermal Effects ◽  
Effective Theory ◽  
Qcd Phase Transition ◽  
First Order ◽  
Pure Gauge ◽  
Qcd Vacuum ◽  
Magnetic Symmetry ◽  
Deconfinement Phase Transition ◽  
Potential Formalism

We study the pure-gauge QCD phase transition at filnite temperatures in the dual QCD theory, an effective theory of QCD based on the magnetic symmetry. We formulate the effective thermodynamical potential for filnite temperatures using the path-integral formalism in order to investigate the properties of the pure-gauge QCD vacuum. Thermal effects bring a first-order deconfinement phase transition.

WETTING OF HOT GLUONS

1992 ◽  
Vol 03 (05) ◽  
pp. 939-946 ◽  
Author(s):  
U.-J. WIESE
Keyword(s):  
Phase Transition ◽  
High Temperature ◽  
Gauge Theory ◽  
Bubble Nucleation ◽  
Polyakov Loop ◽  
Effective Theory ◽  
Complete Wetting ◽  
First Order ◽  
Pure Gauge Theory ◽  
Deconfinement Phase Transition

In the SU(3) pure gauge theory the high temperature deconfinement phase transition is first order. At the transition the confined phase coexists with three distinct deconfined phases. The interfaces separating the various phases show universal critical behavior when the confined phase completely wets the deconfined-deconfined interfaces. The critical exponents of complete wetting are derived from an interface solution of a Z(3) symmetric effective theory for the Polyakov loop. When complete wetting occurs in the pure glue theory the deconfinement transition proceeds via domain wall splitting. When quarks are present wetting disappears and the standard bubble nucleation scenario applies.

COLOR CONFINEMENT AND FINITE TEMPERATURE QCD PHASE TRANSITION

2004 ◽  
Vol 19 (02) ◽  
pp. 271-285 ◽  
Author(s):  
H. C. PANDEY ◽  
H. C. CHANDOLA ◽  
H. DEHNEN
Keyword(s):  
Phase Transition ◽  
Critical Temperature ◽  
Effective Potential ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Zero Temperature ◽  
Expectation Value ◽  
Qcd Phase Transition ◽  
Qcd Vacuum ◽  
Color Confinement

We study an effective theory of QCD in which the fundamental variables are dual magnetic potentials coupled to the monopole field. Dual dynamics are then used to explain the properties of QCD vacuum at zero temperature as well as at finite temperatures. At zero temperature, the color confinement is realized through the dynamical breaking of magnetic symmetry, which leads to the magnetic condensation of QCD vacuum. The flux tube structure of SU(2) QCD vacuum is investigated by solving the field equations in the low energy regimes of the theory, which guarantees dual superconducting nature of the QCD vacuum. The QCD phase transition at finite temperature is studied by the functional diagrammatic evaluation of the effective potential on the one-loop level. We then obtained analytical expressions for the vacuum expectation value of the condensed monopoles as well as the masses of glueballs from the temperature dependent effective potential. These nonperturbative parameters are also evaluated numerically and used to determine the critical temperature of the QCD phase transition. Finally, it is shown that near the critical temperature (Tc≃0.195 GeV ), continuous reduction of vacuum expectation value (VEV) of the condensed monopoles caused the disappearance of vector and scalar glueball masses, which brings a second order phase transition in pure SU(2) gauge QCD.

NUCLEON PROPERTIES IN THE EXPANDING UNIVERSE

2003 ◽  
Vol 18 (02n06) ◽  
pp. 374-383
Author(s):  
W-Y. PAUCHY HWANG
Keyword(s):  
Phase Transition ◽  
Early Universe ◽  
Mass Formula ◽  
The State ◽  
Nucleon Mass ◽  
Expanding Universe ◽  
Qcd Phase Transition ◽  
Qcd Vacuum ◽  
The Universe

Our universe expands and cools. The electroweak (EW) phase transition, which endows masses to the various particles, and QCD phase transition, which gives rise to confinement of quarks and gluons within hadrons in the true QCD vacuum, Would presumably have taken place in the early universe, respectively, at around 10-11 sec and at a time between 10-5 sec and 10-4 sec, or at the temperature of about 300 GeV and of about 150 MeV, respectively. It is clear that the nucleon mass [Formula: see text], the axial coupling [Formula: see text], and other nucleon parameters evolve as the universe evolves, thereby serving as an important gauge for understanding the state of the Universe.

scholarly journals Dark confinement-deconfinement phase transition: a roadmap from Polyakov loop models to gravitational waves

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Zhaofeng Kang ◽  
Jiang Zhu ◽  
Shinya Matsuzaki
Keyword(s):  
Phase Transition ◽  
Gravitational Wave ◽  
Gravitational Waves ◽  
Latent Heat ◽  
Polyakov Loop ◽  
Thermodynamic Quantities ◽  
Point Interactions ◽  
Yang Mills ◽  
First Order ◽  
Deconfinement Phase Transition

Abstract We explore the confinement-deconfinement phase transition (PT) of the first order (FO) arising in SU(N) pure Yang-Mills theory, based on Polyakov loop models (PLMs), in light of the induced gravitational wave (GW) spectra. We demonstrate that the PLMs with the Haar measure term, involving models successful in QCD with N = 3, are potentially incompatible with the large N scaling for the thermodynamic quantities and the latent heat at around the criticality of the FOPT reported from the lattice simulations. We then propose a couple of models of polynomial form, which we call the 4-6 PLM (with four- and six-point interactions among the basic PL fields which have center charge 1) and 4-8 PLM (with four- and eight-point interactions), and discuss how such models can naturally arise in the presence of a heavy PL with charge 2. We show that those models give the consistent thermodynamic and large N properties at around the criticality. The predicted GW spectra are shown to have high enough sensitivity to be probed in the future prospected interferometers such as BBO and DECIGO.

SOME THOUGHTS ON THE COSMOLOGICAL QCD PHASE TRANSITION

2008 ◽  
Vol 23 (30) ◽  
pp. 4757-4777
Author(s):  
W-Y. P. HWANG
Keyword(s):  
Phase Transition ◽  
Scalar Field ◽  
Order Phase Transition ◽  
Domain Walls ◽  
Wall Structure ◽  
Complex Scalar ◽  
Qcd Phase Transition ◽  
First Order ◽  
First Order Phase Transition ◽  
First Order Phase

The cosmological QCD phase transitions may have taken place between 10-5 s and 10-4 s in the early universe offers us one of the most intriguing and fascinating questions in cosmology. In bag models, the phase transition is described by the first-order phase transition and the role played by the latent "heat" or energy released in the transition is highly nontrivial and is being classified as the first-order phase transition. In this presentation, we assume, first of all, that the cosmological QCD phase transition, which happened at a time between 10-5 s and 10-4 s or at the temperature of about 150 MeV and accounts for confinement of quarks and gluons to within hadrons, would be of first-order. Of course, we may assume that the cosmological QCD phase transition may not be of the first-order. To get the essence out of the first-order scenario, it is sufficient to approximate the true QCD vacuum as one of possibly degenerate vacua and when necessary we try to model it effectively via a complex scalar field with spontaneous symmetry breaking. On the other hand, we may use a real scalar field in describing the non-first-order QCD phase transition. In the first-order QCD phase transition, we could examine how and when "pasted" or "patched" domain walls are formed, how long such walls evolve in the long run, and we believe that the significant portion of dark matter could be accounted for in terms of such domain-wall structure and its remnants. Of course, the cosmological QCD phase transition happened in the way such that the false vacua associated with baryons and many other color-singlet objects did not disappear (that is, using the bag-model language, there are bags of radius 1.0 fermi for the baryons) — but the amount of the energy remained in the false vacua is negligible by comparison. The latent energy released due to the conversion of the false vacua to the true vacua, in the form of "pasted" or "patched" domain walls in the short run and their numerous evolved objects, should make the concept of the "radiation-dominated" epoch, or of the "matter-dominated" epoch to be reexamined.

Atomic displacements at and order of all phase transitions in multiferroic YMnO3 and BaTiO3

2009 ◽  
Vol 65 (4) ◽  
pp. 450-457 ◽  
Author(s):  
S. C. Abrahams
Keyword(s):  
Phase Transition ◽  
Phase Transitions ◽  
Cell Volume ◽  
Unit Cell Volume ◽  
Landau Theory ◽  
Unit Cell ◽  
Paramagnetic Phase ◽  
First Order ◽  
Atomic Displacements ◽  
Magnetic Symmetry

Coordinate analysis of the multiple phase transitions in hexagonal YMnO3 leads to the prediction of a previously unknown aristotype phase, with the resulting phase-transition sequence: P63′cm′(e.g.) ↔ P63 cm ↔ P63/mcm ↔ P63/mmc ↔ P6/mmm. Below the Néel temperature T N ≃ 75 K, the structure is antiferromagnetic with the magnetic symmetry not yet determined. Above T N the P63 cm phase is ferroelectric with Curie temperature T C ≃ 1105 K. The nonpolar paramagnetic phase stable between T C and ∼ 1360 K transforms to a second nonpolar paramagnetic phase stable to ∼ 1600 K, with unit-cell volume one-third that below 1360 K. The predicted aristotype phase at the highest temperature is nonpolar and paramagnetic, with unit-cell volume reduced by a further factor of 2. Coordinate analysis of the three well known phase transitions undergone by tetragonal BaTiO3, with space-group sequence R3m ↔ Amm2 ↔ P4mm ↔ Pm\overline 3m, provides a basis for deriving the aristotype phase in YMnO3. Landau theory allows the I ↔ II, III ↔ IV and IV ↔ V phase transitions in YMnO3, and also the I ↔ II phase transition in BaTiO3, to be continuous; all four, however, unambiguously exhibit first-order characteristics. The origin of phase transitions, permitted by theory to be second order, that are first order instead have not yet been thoroughly investigated; several possibilities are briefly considered.

CRITICAL PARAMETERS OF PHASE TRANSITION IN DUAL QCD

2005 ◽  
Vol 20 (13) ◽  
pp. 2743-2752 ◽  
Author(s):  
H. C. CHANDOLA ◽  
DINESH YADAV ◽  
H. C. PANDEY ◽  
H. DEHNEN
Keyword(s):  
Phase Transition ◽  
Flux Tube ◽  
Intermediate Energy ◽  
Critical Parameters ◽  
Critical Flux ◽  
Flux Tubes ◽  
Qcd Vacuum ◽  
Color Confinement ◽  
Magnetic Symmetry ◽  
Dynamical Breaking

Color confinement is studied in dual version of SU (2) color gauge theory using its topological structure and the dynamical breaking of the magnetic symmetry which has been shown to effectively trigger the QCD monopole condensation in a dynamical way. The resulting flux tube structure of the QCD vacuum is explored which has been shown to lead to the perfect dual superconducting nature to the QCD vacuum in its dynamically broken phase. The analysis of the flux tube energy at different hadronic length scales has been shown to lead to the appearance of the strong confinement forces in QCD vacuum at large hadronic distances and an indication for the deconfinement phase at small scales. The analysis of the flux tube energy is then used to compute numerically the critical radius and the critical flux tube density of the phase transition from the flux tube phase to deconfined one inside hadrons. The numerical estimates are shown to be in fairly good agreement with the analytical values. The possible implications of these critical parameters on the formation of QGP as a result of the flux tubes fusion in intermediate energy regime are also discussed.

scholarly journals DARK MATTER AND COSMOLOGICAL QCD PHASE TRANSITION

2007 ◽  
Vol 22 (25n28) ◽  
pp. 1971-1985
Author(s):  
W-Y. P. HWANG
Keyword(s):  
Phase Transition ◽  
Dark Matter ◽  
Domain Walls ◽  
Wall Structure ◽  
Complex Scalar ◽  
Latent Energy ◽  
Qcd Phase Transition ◽  
Qcd Vacuum ◽  
Long Run ◽  
Complex Scalar Field

In this talk, we take the wisdom that the cosmological QCD phase transition, which happened at a time between 10−5 sec and 10−4 sec or at the temperature of about 150 MeV and accounts for confinement of quarks and gluons to within hadrons, would be of first order, i.e., would release latent "heat" or latent energy. I wish to base on two important points, i.e. (1) that we have 25% dark matter in the present Universe, and (2) that when the early universe underwent the cosmological QCD phase transition it released 1.02 × 10gm/cm3 in latent energy huge compared to 5.88 × 109 gm/cm3 radiation (photon) energy, to deduce that the two numbers are in fact closely related. It is sufficient to approximate the true QCD vacuum as one of degenerate θ-vacua and can be modelled effectively via a complex scalar field with spontaneous symmetry breaking. We examine how "pasted" or "patched" domain walls are formed, how such walls evolve in the long run, and we believe that the majority of dark matter could be accounted for in terms of such domain-wall structure and its remnants. The latent energy released due to the conversion of the false vacua to the true vacua, in the form of "pasted" or "patched" domain walls at first and their evolved objects, make it obsolete the "radiation-dominated" epoch or later on the "matter-dominated" epoch.

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