Do light fermions destroy the confinement/deconfinement phase transition

Two phenomena may give rise to a phase transition in nuclear matter at high temperatures or high densities. One is associated with the restoration of SU(2) X SU(2) chiral symmetr, the order parameter for which is the scalar density [ anti psi psi]; the other is the confinement/deconfinement phase transition (CDPT), the order parameter for which is the ''Wilson line'' L = e/sup -F/T/ where F is the free energy of an isolated test quark. It has been shown in lattice gauge theories both in numerical calculations and in the strong coupling high temperature approximation that the SU(2) Yang-Mills theory, i.e., a theory with only gluons, undergoes a CDPT at a temperature of the order of the strong interaction confinement scale Λ. IN SU(3) the pure gluon theory evidently has a first order CDPT. Because of the numerical complexities of introducing fermions into lattice gauge theories and particularly because of difficulties in formulating a chirally invariant lattice version of QCD, much less is known about the chiral symmetry breaking phase transition. It has been suggested that the latter phase transition is connected with the former, but numerical evidence has been based upon such a drastic approximation (the ''quenched'' approximation) that one cannot make definitive statements at present. Indeed, it is not even known what effect, if any, fermions have on the CDPT. It is the purpose of the study reported upon here to address this question in a model lattice gauge theory constructed to imitate the characteristics of the CDPT of SU(3), and including a chemical potential coupled to baryon number density