On the chiral and deconfinement phase transitions in parity-conserving QED(3) at finite temperature

We present some results about the interplay between the chiral and deconfin ement phase transitions in parity-conserving QED(3) (with N flavours of mas sless 4 component fermions) at finite temperature. Following Grignani et al . [11,12], confinement is discussed in terms of an effective sine-Gordon (S G) theory for the timelike component of the gauge field Ag. But whereas in [11,12] the fermion mass m is a Lagrangian parameter, we consider the m = 0 case and ask whether an effective SG theory can again be derived with m re placed by the dynamically generated mass Sigma which appears below T-ch, th e critical temperature for the chiral phase transition. The fermion and gau ge sectors are strongly interdependent, but as a first approximation we dec ouple them by taking Sigma to be a constant, depending only on the constant part (A) over tilde(0) of the gauge field. We argue that the existence of a low-temperature confining phase may be associated with the generation of Sigma; and that, analogously, the vanishing of Sigma for T > T-ch drives th e system to its deconfining phase. The effect of the gauge field dynamics o n mass generation is also indicated. (C) 2000 Elsevier Science B.V. All rig hts reserved.