32nd International Symposium on Lattice Field Theory (Lattice 2014)

Session

Vacuum Structure and Confinement

7

24 Jun 2014, 14:15

Columbia University

Conveners

Vacuum Structure and Confinement: Parallel 3F

• Jeff Greensite (San Francisco State University)

Vacuum Structure and Confinement: Parallel 4F

• Edward Shuryak (Stony Brook)

Vacuum Structure and Confinement: Parallel 5F

• Harry Thacker (University of Virginia)

Vacuum Structure and Confinement: Parallel 6F

• Eduardo Follana Adin (Universidad de Zaragoza)

Vacuum Structure and Confinement: Parallel 7F

• Michael Ogilvie (Washington University)

166. Confinement, the Abelian Decomposition, and the Contribution of Topology to the Static Quark Potential

Dr Nigel Cundy (Seoul National University)

24/06/2014, 14:15

Vacuum Structure and Confinement

Talk

In the past few years, we have presented a new way of considering quark confinement. Through a careful choice of a Cho-Duan-Ge Abelian Decomposition, we can construct the QCD Wilson Loop in terms of an Abelian restricted field. The relationship between the QCD and restricted string tensions is exact; and we do not need to gauge fix, apply any path ordering of gauge links, or additional path...

412. Deconfinement, Chiral Symmetry Breaking and Chiral Polarization

Prof. Ivan Horvath (University of Kentucky)

24/06/2014, 14:35

Vacuum Structure and Confinement

Talk

We examine the feasibility of the proposition that in Nf=0 QCD there is a temperature range (T_c < T < T_ch) where real Polyakov line (deconfined) vacuum exhibits valence spontaneous chiral symetry breaking and dynamical chiral polarization of Dirac eigenmodes.

1. Instanton-dyons induce both the chiral symmetry breaking and confinement

Prof. Edward Shuryak (Stony Brook)

24/06/2014, 14:55

Vacuum Structure and Confinement

Talk

QCD topology -- mostly instantons -- had been used in the past to explain near-zero Dirac states and chiral symmetry breaking. At $T\sim T_c$ instanton are known to get decomposed into $N_c$ instanton-dyons. Several lattice observation were naturally explained by instanton-dyons. Their partition function is now numerically generated: the statistical ensemble is then used to get spectrum of...

218. Partial restoration of chiral symmetry inside hadrons

Dr Takumi Iritani (High Energy Accelerator Research Organization (KEK))

24/06/2014, 15:35

Vacuum Structure and Confinement

Talk

The presence of color source may modify the chiral condensate that characterizes the spontaneous breaking of chiral symmetry in the QCD vacuum. Using the overlap-Dirac eigenmodes, we investigate this phenomenon around static color sources representing quark-antiquark and three-quark systems. We show that the chiral condensate is reduced inside the flux-tube that is formed between the color...

346. Exploring confinement in SU(N) gauge theories with double-trace Polyakov loop deformations

Prof. Michael Ogilvie (Washington University)

24/06/2014, 16:30

Vacuum Structure and Confinement

Talk

Recent results applying resurgence theory to finite-temperature field theories yield a detailed analytic structure determined by topological excitations. We examine finite-temperature SU(N) lattice gauge theories in light of these results. Double-trace Polyakov loop deformations move through different regions of the confined phase characterized by continuous change in the adjoint Polyakov...

396. Magnetic monopole and confinement/deconfinement phase transision in SU(3) Yang-Mills theory

Dr Akihiro Shibata (KEK)

24/06/2014, 16:50

Vacuum Structure and Confinement

Talk

We have proposed the non-Abelian dual super conductivity in SU(3) Yang-Mills (YM) theory for the mechanism of quark confinement, and by using the proposed gauge link decomposition to extract magnetic monopole in the gauge invariant way we presented the evidences in lattice conferences. In this talk, we focus on the dual Meissner effects in view of the magnetic monopole in SU(3)...

418. Zero modes of overlap fermions, instantons and monopoles

Dr Masayasu Hasegawa (Bogoliubov Laboratory of Theoretical Physics, JINR)

24/06/2014, 17:10

Vacuum Structure and Confinement

Talk

Monopoles are considered that play the very important roles for the color confinement mechanism. University of Kanazawa and Pisa groups have shown a number of studies which support the confinement mechanism due to monopole condensations by the lattice simulations. Instantons that are other topological objects found as solutions of QCD. The close relations to chiral symmetry breaking are...

187. Spectral Flow and Index Theorem for Staggered Fermions

Dr Eduardo Follana Adin (Universidad de Zaragoza)

24/06/2014, 17:30

Vacuum Structure and Confinement

Talk

We investigate numerically the spectral flow introduced by Adams for the staggered Dirac operator on realistic quenched gauge configurations in 2D and 4D. We study both the unimproved and the HISQ Dirac operators, and we compare with the case of spectral flow for Wilson fermions. We show that the spectral flow provides a good topological definition of the index, with a clear separation of high...

131. Topological insulators and the QCD vacuum.

Prof. Thacker H. B. (University of Virginia)

24/06/2014, 17:50

Vacuum Structure and Confinement

Talk

There is considerable evidence, based on large $N_c$ chiral dynamics, holographic QCD, and Monte Carlo studies, that the topological structure of the QCD vacuum consists of discrete quasivacua separated by domain walls across which the local value of the topological $\theta$ parameter jumps by $\pm 2\pi$. Topological insulators are condensed matter systems which are bulk insulators with...

253. On the rigid string contribution to the interquark potential

Dr michele caselle (Department of Physics, Torino University)

25/06/2014, 09:00

Vacuum Structure and Confinement

Talk

One of the most interesting recent results on the effective string description of Lattice Gauge Theories is the universality of the first few terms of the effective action. This is a direct consequence of the Lorentz invariance of the underlying LGTs and makes this theory much more predictive than usual effective models in particle physics. Besides the well known Nambu-Goto action, one of...

156. Effective string description of the interquark potential in the 3D U(1) Lattice Gauge Theory

Mr Davide Vadacchino (Università degli Studi di Torino - INFN Sezione di Torino)

25/06/2014, 09:20

Vacuum Structure and Confinement

Talk

The U(1) lattice gauge theory in three dimensions is a perfect laboratory to study the subtle properties of the confining string. On the one hand, thanks to the mapping to a coulomb gas of monopoles, the model can be exactly solved and confinement proven analytically. On the other hand high-precision numerical estimates of Polyakov loop correlators can be obtained via a duality map to a spin...

183. London penetration depth and coherence length of SU(3) vacuum flux tubes

Francesca Cuteri (Università della Calabria, INFN-Cosenza)

25/06/2014, 09:40

Vacuum Structure and Confinement

Talk

The transverse profile of the chromoelectric field generated by a quark-antiquark pair in the SU(3) vacuum is analysed within the dual superconductor scenario, then the London penetration depth and coherence length are extracted. The color field is determined on the lattice through a connected correlator of two Polyakov loops measured on smeared configurations.

316. Anisotropy of the quark anti-quark potential in a magnetic field

Mr Francesco Negro (INFN - Sezione di Pisa)

25/06/2014, 10:00

Vacuum Structure and Confinement

Talk

We determine the static quark anti-quark potential for QCD at the physical point in the presence of an external magnetic field. The potential is anisotropic, in particular it is steeper in the directions orthogonal to the magnetic field than in the parallel one. The string tension increases (decreases) in the orthogonal (parallel) directions; the absolute value of the Coulomb...

112. The static three-quark potential from the Polyakov loop correlation function

Dr Yoshiaki Koma (Numazu College of Technology)

25/06/2014, 10:20

Vacuum Structure and Confinement

Talk

We study the static three-quark potential in SU(3) lattice gauge theory at zero temperature with the Polyakov loop correlation function (PLCF) consisting of three Polyakov loops. Compared to the use of the three-quark Wilson loop, the PLCF allows us to investigate the ground state potential of various three-quark configurations in detail with less systematic effects. We overcome the problem...

42. Testing the Witten–Veneziano mechanism with the Yang–Mills gradient flow on the lattice

Marco Cè (Scuola Normale Superiore, Pisa, Italy and INFN, Sezione di Pisa, Italy)

25/06/2014, 11:10

Vacuum Structure and Confinement

Talk

We present a precise computation of the topological charge distribution in the SU(3) Yang–Mills theory. It is carried out on the lattice with high statistics Monte Carlo simulations by employing the clover discretization of the field strength tensor combined with the Yang–Mills gradient flow. The flow equations are integrated numerically by a fourth-order structure-preserving Runge–Kutta...

383. The Gluon Dyson-Schwinger equation of Lattice Landau Gauge

Dr Andre Sternbeck (University of Regensburg)

25/06/2014, 11:30

Vacuum Structure and Confinement

Talk

We investigate the exact gluonic Dyson-Schwinger equation of quenched SU(n) lattice gauge theory in Landau gauge and the lattice analog of the Kugo-Ojima confinement criterion.

193. Z(N) dependence of the pure Yang-Mills gluon propagator in the Landau gauge near Tc

Dr Paulo Silva (University of Coimbra)

25/06/2014, 11:50

Vacuum Structure and Confinement

Talk

The Z(N) dependence of the pure Yang-Mills gluon propagator, in the Landau gauge, is investigated at finite temperature for N=3. Special attention will be given to the behaviour near the critical temperature Tc. Our simulations show a complex pattern as expected in a first order phase transition. Furthermore, we identify an order parameter directly associated with the breaking of the SU(3)...

13. Smearing Center Vortices

Mr Roman Hoellwieser (NMSU)

25/06/2014, 12:10

Vacuum Structure and Confinement

Talk

We present a method to smear (center projected) Z(2) vortices in order to obtain properties of the original (full) SU(2) configurations. In particular we address the problem that Z(2) configurations cannot be treated with overlap (or chirally improved) fermions due to their lack of smoothness. We develop a method to regain this smoothness and simultaneously maintain the center vortex...

139. Centre Vortex Effects on the Overlap Quark Propagator

Mr Daniel Trewartha (University of Adelaide)

25/06/2014, 12:30

Vacuum Structure and Confinement

Talk

The fundamental aspects of the QCD vacuum that are responsible for the dynamical generation of mass through chiral symmetry breaking is an ongoing source of debate. We investigate the role of centre vortices in dynamical mass generation using overlap fermions. The exact chiral symmetry that the overlap fermion action possesses yields a distinctive response to the underlying topology of the...

127. The dynamical QCD string

Prof. Leonid Glozman Glozman (University of Graz)

26/06/2014, 14:15

Vacuum Structure and Confinement

Talk

Using the overlap Dirac operator we remove its lowest-lying eigenmodes from the valence quark propagators and study evolution of the J=1 meson masses. At the truncation energy about 50 MeV we observe a degeneracy of all possible U(2)_L * U(2)_R multiplets, i.e. the observed quantum levels have a symmetry larger than U(2)_L * U(2)_R and their energy does not depend on the spin...

10. Study of axial magnetic effect

Mr Victor Braguta (IHEP)

26/06/2014, 14:35

Vacuum Structure and Confinement

Talk

The axial magnetic field, which couples to left- and right-handed fermions with opposite signs, may generate an equilibrium dissipationless energy flow of fermions in the direction of the field even in the presence of interactions. In this report numerical observation of the Axial Magnetic Effect in SU(2) lattice gauge theory is presented. The temperature behavior of the Axial Magnetic Effect...

311. Surface operators study within the lattice QCD

Dr Alexander Molochkov (Far Eastern Federal University)

26/06/2014, 14:55

Vacuum Structure and Confinement

Talk

The most important probes for the phase states of a four-dimensional gauge field theory are the Wilson and t'Hooft line operatros that are defined on one-dimensional curves in the space-time. However, for more detail understanding of four-dimensional gauge field theory dynamics and vacuum topology we need additional probes expressed by operators defined on the subspaces with higher dimensions....

432. Screening without dynamical quarks

Prof. Jacek Wosiek (Jagellonian University)

26/06/2014, 15:15

Vacuum Structure and Confinement

Talk

Screening of external charges by electric fluxes induced by periodic boundary conditions in two dimensional gauge theories will be discussed. Subsequently, the less known problem of introducing sources with arbitrary charge, i.e. non-congruent with an elementary one, will be presented and elaborated. Finally the new, classical continuum limit of lattice formulation will be proposed and...

191. two-dimensional phase structure of SU(2) gauge-Higgs model

Mr Shinya Gongyo (Kyoto University)

26/06/2014, 15:35

Vacuum Structure and Confinement

Talk

We study numerically the phase structure in two dimensions with SU(2) gauge-Higgs coupling. We calculate the static potential from Wilson Loop, W propagator and the order parameter related to a transition between the confinement-like phase and Higgs-like phase. Our results suggest that there is a confinement-like phase and Higgs-like phase, even in two dimensions. In the confinement-like...

434. van Baal's legacy: From renormalons to bions

Mithat Unsal (North Carolina State University)

26/06/2014, 15:55

Vacuum Structure and Confinement

Talk

This talk presents a summary of our current understanding of confinement problem in non-abelian gauge theories. It is dedicated to the memory of Pierre van Baal, who contributed to the field significantly. I will review recent semi-classically calculable realization of confinement in various gauge theories. In particular, I will describe the role of monopole-instantons(realized by van...