SCREENING AND DECONFINEMENT OF SOURCES IN FINITE-TEMPERATURE SU(2) LATTICE GAUGE-THEORY

Deconfinement and screening of higher-representation sources in finite -temperature SU(2) lattice gauge theory is investigated by both analyt ical and numerical means. The effective Polyakov-line action at strong coupling is simulated by an efficient cluster-updating Monte Carlo al gorithm for the case of d = 4 dimensions. The results compare very fav ourably with an improved mean-field solution. The limit d --> infinity of the SU(2) theory is shown to be highly singular as far as critical behaviour is concerned. In that limit the leading amplitudes of highe r representation Polyakov lines vanish at strong coupling, and sublead ing exponents become dominant. Each of the higher-representation sourc es then effectively carry with them their own critical exponents.