Sign-problem in heavy-dense QCD

Monte-Carlo simulations of QuantumChromoDynamics at finite baryon densities would provide direct insights into cold but dense matter, as it occurs in compact stars. However, standard Monte-Carlo techniques cannot be applied because of the notorious sign problem. Several strategies have been developed over the years to tackle this problem. In this talk, I will first review the nature of the problem in heavy quark QCD at finite density. Then I will present our recent work based on the density-of-states approach, as proposed by Langfeld, Lucini and Rago.

I will show how quantities such as the quark density can be extracted for a wide range of chemical potentials. I will compare our results with the phase quenched approximation.