QCD thermodynamics with dynamical fermions

TL;DR

This thesis investigates the QCD phase transition at finite temperature and density using large-scale lattice simulations, providing insights into early Universe evolution and heavy ion collision experiments.

Contribution

It presents new lattice simulation results for the QCD phase diagram, equation of state with dynamical quarks, and high-temperature pure gauge theory comparisons.

Findings

QCD phase diagram at small chemical potentials determined

Equation of state with 2+1 dynamical quarks analyzed

Pure gauge theory equation of state extended to high temperatures

Abstract

In this thesis the finite temperature transition between confined and deconfined matter is studied at zero and nonzero quark densities. The findings are relevant for the understanding of the evolution of the early Universe and contemporary and upcoming heavy ion experiments. The results were obtained using large-scale simulations on lattices with various physical extents and lattice spacings, at physical values of the parameters of the theory. First the phase diagram of QCD in the chemical potential-temperature plane is determined for small chemical potentials via a Taylor-expansion technique. Second the equation of state is studied with 2+1 flavors of dynamical quarks. Finally, the equation of state is calculated in pure gauge theory up to extremely high temperatures, where a comparison to perturbation theory is carried out.