CHIRAL DISORDER AND QCD AT FINITE CHEMICAL-POTENTIAL

We investigate the effects of a finite chemical potential FL in QCD vi ewed as a disordered medium. In the quenched approximation, A(4) = i m u induces a complex electric Aharonov-Bohm effect that causes the diag onal contribution to the quark return probability to vanish at mu = m( pi)/2 (half the pion mass). In two-color QCD, the weak-localization co ntribution to the quark return probability remains unaffected causing a mutation in the spectral statistics. In full QCD, the complex electr ic flux is screened and the light quarks are shown to diffuse asymmetr ically with a substantial decrease in the conductivity along the 'spat ial' directions. Mean-field arguments suggest that a d = 1 percolation transition may take place in the range 1.5 rho(o) < rho < 3 rho(o), w here rho(o) is nuclear matter density. (C) 1998 Elsevier Science B.V. All rights reserved.