Mon·Sep 2, 2002Monday·September 2, 2002

1. 01*

   Center Symmetry and Abelian Projection at Finite Temperature

   Michael C. Ogilvie🇺🇸

   At finite temperature, there is an apparent conflict between Abelian projection and critical universality. For example, should the deconfinement transition of an SU(2) gauge theory projected to U(1) lie in the Z(2) universality class of the parent SU(2) theory or in the U(1) universality class? I prove that the projected theory lies in the universality class of the parent gauge theory. The mechanism is shown to be non-local terms in the projected effective action involving Polyakov loops. I connect this to the recent work by Dunne et al. on the deconfinement transition in the 2+1 dimensional Georgi-Glashow model.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·2 citations
2. 02*

   A Phenomenological Treatment of Chiral Symmetry Restoration and Deconfinement

   Peter N. Meisinger🇺🇸 · Travis R. Miller🇺🇸 · Michael C. Ogilvie🇺🇸

   A phenomenological expression for the thermodynamic potential of gluons and quarks is constructed which incorporates the features of deconfinement and chiral symmetry restoration known from lattice simulations. The thermodynamic potential is a function of the Polyakov loop and chiral condensate expectation values. The gluonic sector uses a successful model for pure (SU(N_c)) gauge theories in which the Polyakov loop eigenvalues are the fundamental order parameters for deconfinement. The quark sector is given by a Nambu-Jona-Lasinio model in which a constant background (A_0) field couples the chiral condensate to the Polyakov loop. We consider the case of (N_f = 2) in detail. For two massless quarks, we find a second order chiral phase transition. Confinement effects push the transition to higher temperatures, but the entropy associated with the gluonic sector acts in the opposite direction. For light mass quarks, only a rapid crossover occurs. For sufficiently heavy quarks, a first order deconfinement transition emerges. This simplest model has one adjustable parameter, which can be set from the chiral transition temperature for light quarks. It predicts all thermodynamic quantities as well as the behavior of the chiral condensate and the Polyakov loop over a wide range of temperatures.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·12 citations
3. 03*

   Numerical studies of confinement in the Landau gauge by the larger lattice simulation

   Hideo Nakajima🇯🇵 · Sadataka Furui🇯🇵

   Figure 1 and Figure 2(right) are replaced and the slope parameter ${\alpha }_D$ is corrected to -0.4.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·13 citations
4. 04*

   Screening of hot gluon

   A. Nakamura🇯🇵 · I. Pushkina🇯🇵 · T. Saito🇯🇵 · S. Sakai🇯🇵

   We calculate electric and magnetic masses of gluons between T = T_c and 6T_c using lattice QCD (quantum chromodynamics) in the quench approximation. We find that magnetic mass has finite values in this region, and the temperature dependence of the electric mass is consistent with that determined using the hard-thermal-loop perturbation. The hard-thermal-loop resummation improves significantly the magnitude of the electric mass comparing to the leading order perturbation. Both screening masses have little gauge dependence.

   hep-lathep-phPLB(2002)·18 citations
5. 05*

   SU(2) Lattice Gauge Theory at Nonzero Chemical Potential and Temperature

   John B. Kogut

   SU(2) lattice gauge theory with four flavors of quarks is simulated at nonzero chemical potential mu and temperature T and the results are compared to the predictions of Effective Lagrangians. Simulations on 16^4 lattices indicate that at zero T the theory experiences a second order phase transition to a diquark condensate state which is well described by mean field theory. Nonzero T and mu are studied on 12^3 times 6 lattices. For low T, increasing mu takes the system through a line of second order phase transitions to a diquark condensed phase. Increasing T at high mu, the system passes through a line of first order transitions from the diquark phase to the quark-gluon plasma phase.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·9 citations
6. 06*

   QCD in Extreme Environments

   John B. Kogut🇺🇸

   I review present challenges that QCD in extreme environments presents to lattice gauge theory. Recent data and impressions from RHIC are emphasized. Physical pictures of heavy ion wavefunctions, collisions and the generation of the Quark Gluon Plasma are discussed, with an eye toward engaging the lattice and its numerical methods in more interaction with the experimental and phenomenological developments. Controversial, but stimulating scenarios which can be confirmed or dismissed by lattice methods are covered. In the second half of the talk, several promising developments presented at the conference Lattice 2002 are reviewed.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·16 citations
7. 07*

   The QCD equation of state at nonzero densities: lattice result

   Z. Fodor🇭🇺 · S.D. Katz🇩🇪 · K.K. Szabo🇭🇺

   In this letter we give the equation of state of QCD at finite temperatures and densities. The recently proposed overlap improving multi-parameter reweighting technique is used to determine observables at nonvanishing chemical potentials. Our results are obtained by studying n_f=2+1 dynamical staggered quarks with semi-realistic masses on N_t=4 lattices.

   hep-lathep-phnucl-thPLB(2003)·244 citations
8. 08*

   Improved performance of QCD code on ALiCE

   Z. Sroczynski🇩🇪

   We present results for the performance of QCD code on ALiCE, the Alpha-Linux Cluster Engine at Wuppertal. We describe the techniques employed to optimise the code, including the metaprogramming of assembler kernels, the effects of data layout and an investigation into the overheads incurred by the communication.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·3 citations
9. 09*

   The deconfining phase transition in SU(N) gauge theories

   B. Lucini🇬🇧 · M. Teper🇬🇧 · U. Wenger (Oxford University)🇬🇧

   We report on our ongoing investigation of the deconfining phase transition in SU(4) and SU(6) gauge theories. We calculate the critical couplings while taking care to avoid the influence of a nearby bulk phase transition. We determine the latent heat of the phase transition and investigate the order and the strength of the transition at large N. We also report on our determination of the critical temperature expressed in units of the string tension in the large N limit.

   hep-latNucl.Phys.B Proc.Suppl.(2003)·4 citations
10. 10*

    Facets of confinement and dynamical chiral symmetry breaking

    P. Maris🇺🇸 · A. Raya🇲🇽 · C.D. Roberts🇺🇸 · S.M. Schmidt🇩🇪

    The gap equation is a cornerstone in understanding dynamical chiral symmetry breaking and may also provide clues to confinement. A symmetry-preserving truncation of its kernel enables proofs of important results and the development of an efficacious phenomenology. We describe a model of the kernel that yields: a momentum-dependent dressed-quark propagator in fair agreement with quenched lattice-QCD results; and chiral limit values: f_pi= 68 MeV and <q-bar q> = -(190 MeV)^3. It is compared with models inferred from studies of the gauge sector.

    ↳ nucl-thhep-lathep-phEPJA(2003)·77 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.