The EOS of the Quark-Gluon Plasma from Lattice QCD

The quark-gluon plasma is a state of matter which forms at very high temperatures or densities. It is believed that up to microseconds after the big bang the quark-gluon plasma was a dominant component of the universe. This state of matter is recreated in heavy-ion collision experiments (such as RHIC and LHC) which study its formation and transition to ordinary matter. The equation of state of the quark-gluon plasma is essential to our understanding of its hydrodynamic expansion and consequently of the particle spectra produced in these experiments. I present results for the quark-gluon equation of state determined from lattice QCD, which is the only nonperturbative method currently allowing a first principle calculation of its properties.