Quasi-local Update Algorithms for Numerical Simulations of d=3 SU(2) LGT in the Dual Formulation

In the dual formulation of d=3 SU(2) LGT, the link variables are group representations and valid configurations are those satisfying a number of triangle inequalities. In \cite{lat99} algorithms for local updates that automatically respect these constraints were described. It was also pointed out there that these local updates were not ergodic. In this presentation, we describe two different quasi-local updating algorithms which, in conjunction with the local updates, appear to be ergodic.Comment: LATTICE2000(Topics in Gauge Theories),5 pages,5 figures,LaTe

Reformulating Yang-Mills theory in terms of local gauge invariant variables

An explicit canonical transformation is constructed to relate the physical subspace of Yang-Mills theory to the phase space of the ADM variables of general relativity. This maps 3+1 dimensional Yang-Mills theory to local evolution of metrics on 3 manifolds.Comment: Lattice 2000 (Gravity and Matrix Models) 3 pages, espcrc2.st

Unitary and Renormalizable Theory of Higher Derivative Gravity

In 3+1 space-time dimensions, fourth order derivative gravity is perturbatively renormalizable. Here it is shown that it describes a unitary theory of gravitons (with/without an additional scalar) in a limited coupling parameter space which includes standard cosmology. The running of gravitational constant which includes contribution of graviton is computed. It is shown that generically Newton's constant vanishes at short distance in this perturbatively renormalizable and unitary theory.Comment: 4 pages. To appear in JPCS-IOP. Proceedings of the conference COSGRAV12, held at Indian Statistical Institute, Kolkat

Quark Propagator and Chiral Symmetry with String Tension

General properties of the light and heavy quark propagators have been investigated in the context of string tension interaction. Confinement, chiral symmetry breaking, spectral properties of the propagator are analytically studied and numerically validated. We show that the propagator is analytic in the infrared region even for massless quarks with a non zero radius of convergence. Emergence of more than one mass scale is exemplified. Massless limit of the quark propagator does exhibit critical behaviour.Comment: 15 pages, 6 eps figures, LaTe

Charge Renormalization due to Graviton Loops

The leading term in the gauge coupling beta function comes due to interaction of gauge field with gravitons. It is shown to be a universal quantity for all gauge theories. At one-loop it is found to be zero in four dimensions. This is independent of the gravity action with metric as the field variable, gauge fixing condition and regularization scheme. This term being universally same for all gauge groups is further studied in the case of abelian gauge theories, where due to self-duality this term is shown to be zero to all loops, on-shell. Consequences of this are discussed.Comment: 1+10 pages, 1 figure, Published in JHE

Analytic Variational Investigation of Euclidean SU(3) Gauge Theory

Analytic variational techniques for lattice gauge theories based on the Rayleigh-Ritz(RR) method were previously developed for euclidean SU(2) gauge theories in 3 and 4 dimensions. Their extensions to SU(3) gauge theory including applications to correlation functions and mass gaps are presented here.Comment: 4-pages in 2-column format, typsetted for LaTeX with document style espcrc2.sty (available on request), IMSc/93-2