Confinement: Understanding the Relation Between the Wilson Loop and Dual Theories of Long Distance Yang Mills Theory

In this paper we express the velocity dependent, spin dependent heavy quark potential $V_{q\bar q}$ in QCD in terms of a Wilson Loop $W(\Gamma)$ determined by pure Yang Mills theory. We use an effective dual theory of long-distance Yang Mills theory to calculate $W(\Gamma)$ for large loops; i.e. for loops of size $R > R_{FT}$. ($R_{FT}$ is the flux tube radius, fixed by the value of the Higgs (monopole) mass of the dual theory, which is a concrete realization of the Mandelstam 't Hooft dual superconductor mechanism of confinement). We replace $W(\Gamma)$ by $W_{eff}(\Gamma)$, given by a functional integral over the dual variables, which for $R > R_{FT}$ can be evaluated by a semiclassical expansion, since the dual theory is weakly coupled at these distances. The classical approximation gives the leading contribution to $W_{eff}(\Gamma)$ and yields a velocity dependent heavy quark potential which for large $R$ becomes linear in $R$, and which for small $R$ approaches lowest order perturbative QCD. This latter fact means that these results should remain applicable down to distances where radiative corrections giving rise to a running coupling constant become important. The spin dependence of the potential reflects the vector coupling of the quarks at long range as well as at short range. The methods developed here should be applicable to any realization of the dual superconductor mechanism. They give an expression determining $W_{eff}(\Gamma)$ independent of the classical approximation, but semi classical corrections due to fluctuations of the flux tube are not worked out in this paper. Taking these into account should lead to an effective string theory free from the conformal anomaly.Comment: 39 pages, latex2e, 1 figure(fig.eps

Excerpts from selected LANDSAT 1 final reports in geology

The standard formats for the summaries of selected LANDSAT geological data are presented as checklists. These include: (1) value of LANDSAT data to geology, (2) geologic benefits, (3) follow up studies, (4) cost benefits, (5) optimistic working scales, (6) statistical analysis, and (7) enhancement effects

Collision of Viscoelastic Spheres: Compact Expressions for the Coefficient of Normal Restitution

The coefficient of restitution of colliding viscoelastic spheres is analytically known as a complete series expansion in terms of the impact velocity where all (infinitely many) coefficients are known. While beeing analytically exact, this result is not suitable for applications in efficient event-driven Molecular Dynamics (eMD) or Monte Carlo (MC) simulations. Based on the analytic result, here we derive expressions for the coefficient of restitution which allow for an application in efficient eMD and MC simulations of granular Systems.Comment: 4 pages, 4 figure

Structures of K0.05Na0.95NbO3 (50–300 K) and K0.30Na0.70NbO3 (100–200 K)

Rietveld refinement using neutron powder diffraction data is reported for the potential lead-free piezoelectric material KxNa1 - xNbO3 (x = 0.05, x = 0.3) at low temperatures. The structures were determined to be of rhombohedral symmetry, space group R3c, with the tilt system a-a-a- for both compositions. It was found that some of the structural parameters differ significantly in the two structures, and particularly the NbO6 octahedral strains as a function of temperature. The 300 K profile for K0.05Na0.95NbO3 shows the coexistence of rhombohedral and monoclinic phases, which indicates that the phase boundary is close to room temperature; the phase boundary for K0.30Na0.70NbO3 is found to be at approximately 180 K

The qqˉq \bar{q} relativistic interaction in the Wilson loop approach

We study the $q \bar{q}$ relativistic interaction starting from the Feynman-Schwinger representation of the gauge-invariant quark-antiquark Green function. We focus on the one-body limit and discuss the obtained non-perturbative interaction kernel of the Dirac equation.Comment: 5 pages, Latex (espcrc2.sty) To be published in the proceedings of High-Energy Physics International Euroconference on Quantum Chromodynamics:QCD97; 25th Anniversary of QCD, Montpellier, France, 3-9 July 199

Interparticle Potential up to Next-to-leading Order for Gravitational, Electrical, and Dilatonic Forces

Long-range forces up to next-to-leading order are computed in the framework of the Einstein-Maxwell-dilaton system by means of a semiclassical approach to gravity. As has been recently shown, this approach is effective if one of the masses under consideration is significantly greater than all the energies involved in the system. Further, we obtain the condition for the equilibrium of charged masses in the system.Comment: 19 pages, 19 figures, RevTeX4.1. Revised version, Title change