FIRST-ORDER PHASE-TRANSITION IN FINITE-DENSITY QCD USING THE MODULUS OF THE DIRAC DETERMINANT

We report results of simulations of strong coupling, finite density QC D obtained within a MFA inspired approach where the fermion determinan t in the integration measure is replaced by its absolute value. Contra ry to the standard wisdom, we show that within this approach a clear s ignal for a first order phase transition appears with a critical chemi cal potential in extremely good agreement with the results obtained wi th the Glasgow algorithm. The modulus of the fermion determinant seems therefore to preserve some of the relevant physical properties of the system. We also analyze the dependence of our results on the quark ma ss, including both the chiral and large mass limit, and the theory in the quenched approximation. (C) 1998 Elsevier Science B.V. All rights reserved.