- [Show abstract] [Hide abstract] ABSTRACT: Using generic properties of string theories, we show how interesting non-perturbative features of QCD can be exploited in heavy ion collisions. In particular, a generalized "semi-circle" law for the phase diagram in the temperature-chemical potential plane is derived.
- [Show abstract] [Hide abstract] ABSTRACT: We study the Abelian projection of an instanton in R3 × S1 as a function of temperature (T) and non-trivial holonomic twist (ω) of the Polyakov loop at infinity. These parameters interpolate between the circular monopole loop solution at T = 0 and the static 't Hooft-Polyakov monopole/anti-monopole pair at high temperature.
- [Show abstract] [Hide abstract] ABSTRACT: We investigate the Maximally Abelian (MA) Projection for a single $SU(2)$ instanton in continuum gauge theory. We find that there is a class of solutions to the differential MA gauge condition with circular monopole loops of radius $R$ centered on the instanton of width $\rho$. However, the MA gauge fixing functional $G$ decreases monotonically as $R/\rho \rightarrow 0$. Its global minimum is the instanton in the singular gauge. We point out that interactions with nearby anti-instantons are likely to excite these monopole loops. Comment: Talk presented at LATTICE96(topology), 3 pages, 2 EPS figures, needs espcrc2.sty
- [Show abstract] [Hide abstract] ABSTRACT: We consider a particular 4 state spin system composed of two Ising spins (~$s_x, \; \sigma_x$~) with independent hopping parameters $\kappa_1, \kappa_2$, coupled by a bilinear Yukawa term, $y s_x \sigma_x$. The Yukawa term is solely responsible for breaking the global $ Z_2 \times Z_2$ symmetry down to $Z_2$. This model is intended as an illustration of general coupled Higgs system where scalars can arise both as composite and elementary excitations. For the Ising example in 2d, we give convincing numerical evidence of the universality of the two spin system with the one spin Ising model, by Monte Carlo simulations and finite scaling analysis . We also show that as we approach the phase transition, universality arises by a separation of low mass spin waves from an extra set of spin waves with an energy gap that diverges as the correlations length diverges
- [Show abstract] [Hide abstract] ABSTRACT: The large-N saddle-point equations for the principal chiral models defined on a d-1 dimensional simplex are derived from the external field problem for unitary integrals. The saddle point equation are studied analytically and numerically in many relevant instances, including d=4 and $d\rightarrow\infty$, with special attention to the critical domain, which is found to correspond to $\beta_c=1/d$ for all d. Related models (chiral chains) are discussed and large-N solutions are analyzed. Comment: 47 pages + 4 figures in an uuencoded file
Article: The chiral extension of lattice QCD[Show abstract] [Hide abstract] ABSTRACT: The chiral extension of Quantum Chromodynamics (XQCD) adds to the standard lattice action explicit pseudoscalar meson fields for the chiral condensates. With this action, it is feasible to do simulations at the chiral limit with zero mass Goldstone modes. We review the arguments for why this is expected to be in the same universality class as the traditional action. We present preliminary results on convergence of XQCD for naive fermions and on the methodology for introducing counter terms to restore chiral symmetry for Wilson fermions.