出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We study the sign problem of the fermion determinant at nonzero baryon chemical potential. For
this purpose we apply a simple model derived from Quantum Chromodynamics, in the limit of
large chemical potential and mass. For SU(2) color, there is no sign problem and the mean-field
approximation is similar to data from the lattice. For SU(3) color the sign problem is unavoidable,
even in a mean-field approximation. We apply a phase-reweighting method, combined with the
mean-field approximation, to estimate thermodynamic quantities. We also investigate the meanfield
free energy using a saddle-point approximation [1].
