Calculating the equation of state of dense quark-gluon plasma using the complex Langevin equation

摘要

The pressure and energy density of the quark-gluon plasma at finite baryon chemical potential are calculated using the complex Langevin equation. The stout smearing procedure is generalized for the SL ( 3 , C ) manifold allowing the usage of an improved action in the complex Langevin setup. Four degenerate flavors of staggered quarks with m π = 500 – 700 ? ? MeV are used with a tree-level Symanzik improved gauge action on 1 6 3 × 8 lattices. Results are compared to the Taylor expansion and good agreement is found for small chemical potentials.