Macroscopic Universality : Why QCD in Matter is Subtle?

Abstract

We use a chiral random matrix model with 2N_f flavors to mock up the QCD Dirac spectrum at finite chemical potential. We show that the 1/N approximation breaks down in the quenched state with spontaneously broken chiral symmetry. The breakdown condition is set by the divergence of a two-point function, that is shown to follow the general lore of macroscopic universality. In this state, the fermionic fluctuations are not suppressed in the large N limit.

Comments: Title changed in published version