2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/40061The lecture provides an introduction to thermal field theory and its applications to the physics of the quark-gluon plasma, possibly created in relativistic heavy ion collisions. In particular the Hard Thermal Loop resummation technique, providing a consistent perturbative description of relativistic, high-temperature plasmas is introduced. Using this method interesting quantities of the quark-gluon plasma (damping rates, energy loss, photon and dilepton production) are discussed. Furthermore recent developments on non-equilibrium field theory, which are relevant for high-energy heavy ion physics, are presented.46 pages, 38 figures, Lecture notes of the Jyvaskyla Summer School 2000High Energy Physics - PhenomenologyNuclear Theorytext