TIFR Annual Report 1999-00 THEORETICAL PHYSICS High Energy Physics

The effect of Z2 magnetic monopoles and vortices on the finite temperature deconfinement phase transition in the fundamental-adjoint Villain form of SU(2) lattice gauge theory has been investigated. A complete suppression of the Z2 monopoles has been shown to lead to an action for the theory which is self-dual under the exchange of the fundamental and adjoint couplings. By further suppressing the Z2 vortices the theory has been reduced to the usual Wilson action but with a modified coupling. The universality of the SU(2) deconfinement phase transition with the 3-dimensional Ising model should therefore remain intact in the entire plane of the fundamental-adjoint couplings in the continuum limit. Generalizations of these arguments to the SU(N) theory have been outlined. (R. V. Gavai and Manu Mathur, SNBNCBS, Calcutta)