共查询到20条相似文献,搜索用时 31 毫秒
1.
We perform a high statistics Monte Carlo calculation of the string tension in the twisted SU(N) Eguchi-Kawai model for N=36 and N=64. The string tension, calculated from Wilson loops not larger than 3 × 3, clearly shows the renormalization group scaling behaviour. 相似文献
2.
The well-understood roughening transition of an interface in the d = 3 Ising model implies an essential singularity in the string tension of the dual Z2 gauge model. The roughening transition corresponds to the delocalization of the string due to strong long-wavelength fluctuations, and this reformulation can be generalized to other gauge groups and to d = 4 also. It is not a deconfining transition - it is expected to occur deep in the confining region - but its presence would raise serious questions about the continuation of strong coupling expansions of the tension beyond this point. In this paper predictions on the roughening transition are confronted with the available information on the string tension for different gauge groups in three dimensions. 相似文献
3.
A.A. Migdal M.I. Polikarpov A.I. Veslov V.P. Yurov T.A. Kozhamkulov A.N. Varlamova 《Nuclear Physics B》1984,243(2):212-220
The Langevin equation at the group manifolds is derived and investigated for the twisted Eguchi-Kawai model The numerical results for the string tension for various values of N are combined with the known Monte Carlo results to give an improved value of the string tension. The distribution of eigenvalues of Wilson loop matrices are also studied. 相似文献
4.
Cluster expansion methods are applied to theSU(2) lattice gauge model in (2+1) dimensions. Strong-coupling series are calculated for the vacuum energy per site, the axial string tension, and the scalar mass gap; while ELCE approximants are used to estimate the string tension beyond its roughening transition. The simple scaling behaviour expected of this super-renormalizable theory is clearly seen, and we estimate that in the continuum limit the string tension σ~(0.14±0.01)g 4, while the mass gapM s ~(2.2±0.25)g 2. More accurate Monte Carlo simulations are needed to check the universality between the Hamiltonian and Euclidean versions of this model. 相似文献
5.
Compact U(1) lattice gauge theory is studied in 2 + 1 and 3 + 1 dimensions using strong coupling series expansions and the recently proposed exact linled cluster expansion alborithm Results for the vacuum energy, specific heat and axial string tension in 2 + 1 dimensions are in agreement with previous finite lattice estimates. In 3 + 1 dimensions, we present new strong coupling series results (order g?40) which together with the ELCE estimates show evidence of a continuous phase transition at x = 1/g4 = 0.72 ± 0.08. The associated critical index for the vanishing string tension is μ = 0.65 ± 0.12. The axial string tension in D = 3 + 1 appears to undergo a non-deconfining roughening transition at smaller x (0.56 ± 0.07). 相似文献
6.
We study the width of the confining string between static quarks in abelian lattice gauge theories using strong coupling expansions. We consider gauge groups Zn and U(1) in 3 and 4 dimensions. This extends previous work with Lüscher, where SU(2) and Z2 were studied. In ν = 3 dimensions we find evidence for a roughening transition. It is characterized by a divergence of the string width for an infinitely far separated quark-antiquark pair, while the string tension remains non-zero. In ν = 4 dimensions for the abelian groups we do not have evidence for a roughening transition away from a phase transition. 相似文献
7.
The partition function ofd dimensional systems is estimated with the help of a variational Ansatz in terms of quasi-(d-1)-dimensional systems. The internal energy and the string tension derived in this framework agree reasonably with the Monte Carlo data. 相似文献
8.
J. Hoek 《Zeitschrift fur Physik C Particles and Fields》1987,35(3):369-377
Wilson loops are calculated on 324 lattices in the coupling regime 6/g 2=6.3–6.9. Determination of the string tension from these loops with a method based on string model calculations shows a string tension that does not seem to scale. This is probably due to the amount of statistics. It points to difficulties in obtaining accurate physical results for coupling values above 6.6. Suggestions to improve this situation are made. 相似文献
9.
We determine numerically, and display graphically, the electromagnetic energy distribution due to static sources in compact QED3. Using the polymer formulation of the functional integral, Monte Carlo simulations are performed with external sources included in the lattice action. Both the Wilson and Villain forms of the action are studied, and the string tension is determined in a small range of weak couplings. For the Villain action, our values for the string tension σ are in agreement with Polyakov's formula. For the Wilson action, we are able to detect a string tension in a range of weak couplings 2.1 ? β ? 2.3 below the weak-to-strong coupling cross-over point. In the same range, standard Monte Carlo results for up to 8 × 8 Wilson loops are consistent with ordinary perturation theory (no confinement). A possible explanation of this discrepancy is discussed, and it is suggested that the standard (source-free) Monte Carlo might miss configurations which are important for flux-tube formation. 相似文献
10.
《Physics letters. [Part B]》1987,191(3):275-281
Exact plane wave solutions of d = 10, N = 1 Einstein-Yang-Mills supergravity theory are presented and their possible modifications in superstring effective theories are examined. It is found that the solutions are not affected by any of the known heterotic string corrections. It is argued that plane waves satisfy the effective field equations of the heterotic string theory in all powers of the string tension parameter α′, possibly after including a totally antisymmetric torsion field and reinterpreting the constants. Similar remarks also apply for type I superstrings. Further properties of the solutions are discussed. 相似文献
11.
《Nuclear Physics B》1988,307(3):512-530
Quarks and gluons in the vacuum background field with a finite correlation length d are shown to be linearly confined inside white states. The string tension for an arbitrary representation of SU(N) is obtained in terms of d and the gluon condensate and agrees with numerical data and large N behaviour. The QCD string picture is shown to emerge asymptotically at large euclidean distances. 相似文献
12.
K.J.M. Moriarty 《Physics letters. [Part B]》1981,102(1):53-54
Monte Carlo simulations of the string tension are calculated for four-dimensional U(1) gauge theory on a 64 lattice. The string tension follows the result -1n(β/2) in the high temperature region and is zero for β > βc, where βc is the critical inverse temperature. 相似文献
13.
Frédéric Jugeau 《Annals of Physics》2010,325(8):1739-1789
It is known, since the 70s, that the large N 't Hooft limit of gauge theories is related to string theories. In 1998, J. M. Maldacena identified precisely such a relation: the so-called AdS/CFT correspondence which speculates a duality between a large N strongly-coupled supersymmetric and conformal Yang-Mills theory in four dimensions and a weakly-coupled string theory defined in a five-dimensional anti-de Sitter AdS5 space-time. This review aims at introducing concepts and methods used to derive, in the framework of the gauge/string correspondence, the interaction potentials of mesons and baryons at zero and finite temperature. The dual string configurations associated with the different kinds of hadrons are described and their behaviours at short and large distances are understood. Although the application of Maldacena's AdS/CFT conjecture to QCD is not straightforward, QCD being neither supersymmetric nor conformal, the AdS/QCD correspondence approach attempts to identify the dual theory of QCD. Especially, the study of heavy quark-antiquark bound-states leads to establish general dual criteria for the confinement. 相似文献
14.
Monte Carlo results for the pure U(3) lattice gauge theory on a 64 lattice are reported. Wilson loops and the string tension are presented. The first-order phase transition in U(3) is reflected quite clearly in a discontinuity in the string tension at β = βc. The U(1) factor of U(3) is extracted using the determinant of the Wilson loops. As expected, the U(1) component appears to deconfine at the phase transition.. 相似文献
15.
16.
Gernot Münster 《Physics letters. [Part B]》1980,95(1):59-62
We present results of high temperature expansions up to order g?24 for the vortex free energy respectively string tension in pure lattice gauge theories with gauge groups SU(2) and Z2 in 3 and 4 dimensions. For SU(2) in 4 dimensions the result is compared with Monte Carlo calculations of Creutz and is in good agreement. An intermediate coupling region is seen, where the string tension smoothly interpolates between strong coupling and weak coupling behaviour. 相似文献
17.
We describe in detail predictions of the QCD string approach for the masses of the heavy—light D, D s , B, and B s mesons, including orbitally and radially excited states. We discuss the role of the proper dynamics of the QCD string in the formation of the spectrum of the heavy—light mesons, with quark self-energy corrections calculated self-consistently in the same picture. We give our predictions in terms of the current quark masses; the string tension—the only dimensional parameter describing the interquark interaction; and the strong coupling constant, which differs for the fine and the hyperfine interactions. The results are compared with the predictions of other models and with the experimental and lattice results. 相似文献
18.
Weak coupling perturbative calculations of the Wilson loop in lattice gauge theory are carried out numerically up to order g4. Comparison of the results with those of the Monte Carlo calculations shows that there exists a non-perturbative contribution of an essential singularity type which may be identified as the string tension. 相似文献
19.
《Physics letters. [Part B]》1988,205(4):535-539
We study the scaling behaviour of lattice quantum chromodynamics by comparing the β dependence of the string tension and the 0++ glueball mass. We use a source method at β=5.7, β=5.9 and β=6.1, on lattices from 93· 24 to 163· 32. Assuming a string tension of about (420 MeV)2, the lattice spacing ranges from 0.16 to 0.08 fm. In order to separate finite volume from scaling violation effects we have compared data from lattices having approximately the same overall physical size at the different values of β. We find deviations from scaling to be very small. 相似文献
20.
K. A. Bugaev A. I. Ivanytskyi E. G. Nikonov V. K. Petrov A. S. Sorin G. M. Zinovjev 《Physics of Atomic Nuclei》2012,75(6):707-709
We discuss some ideas resulting from a phenomenological relation recently declared between the tension of string connecting the static quark-antiquark pair and surface tension of corresponding cylindrical bag. This relation analysis leads to the temperature of vanishing surface tension coefficient of the QGP bags at zero baryonic charge density as T ?? = 152.9 ± 4.5 MeV. We develop the view point that this temperature value is not a fortuitous coincidence with the temperature of (partial) chiral symmetry restoration as seen in the lattice QCD simulations. Besides, we argue that T ?? defines the QCD (tri)critical endpoint temperature and claim that a negative value of surface tension coefficient recently discovered is not a sole result but is quite familiar for ordinary liquids at the supercritical temperatures. 相似文献