Related papers: On Effective Degrees of Freedom in the Early Unive…
We update the curves of the effective degrees of freedom for the energy density $g_*(T)$ and for the entropy density $g_{*S}(T)$ during the era of radiation domination in the Universe. We find that a plain count of effective degrees of…
The effective degrees of freedom of the Quark-Gluon Plasma are studied in the temperature range $\sim 1-2$ $ T_c$. Employing lattice results for the pressure and the energy density, we constrain the quasiparticle chiral invariant mass to be…
This dissertation aims to deepen the understanding of the primordial composition of the Universe in the temperature range 300 MeV>T>0.02 MeV. I exploit known properties of elementary particles and apply methods of kinetic theory and…
In the standard picture of cosmology it is predicted that a phase transition, associated with chiral symmetry breaking after the electroweak transition, has occurred at approximately 10 \mu seconds after the Big Bang to convert a plasma of…
Collisions of heavy nuclei at very high energies offer the exciting possibility of experimentally exploring the phase transformation from hadronic to partonic degrees of freedom which is predicted to occur at several times normal nuclear…
The Equation of State and the properties of matter in the high temperature deconfined phase are analyzed by a quasiparticle approach for $T> 1.2~T_c$. In order to fix the parameters of our model we employ the lattice QCD data of energy…
A standard picture in cosmology has been emerging over the past decade in which a phase transition, associated with chiral symmetry breaking after the electroweak transition, has occurred at approximately $10^{-6}$ seconds after the Big…
These lectures are an introduction to recent developments in the study of the high temperature phase of QCD by using weak coupling techniques. After a brief introduction to some techniques of quantum field theory at finite temperature, I…
We study, in the PNJL model, how the entropy of interacting quarks reflects the change in the effective degrees of freedom as the temperature increases through the quark-hadron phase transition. With inclusion of mesonic correlations, the…
When the universe was about 10 $\mu $seconds old, a first order cosmological quark - hadron phase transition occurred at a critical temperature of around 200 MeV. In this work, we study the quark-hadron phase transition in the context of…
Collisions between heavy atomic nuclei at ultra-relativistic energies are carried out at particle colliders to produce the quark-gluon plasma, a state of matter where quarks and gluons are not confined into hadrons, and colour degrees of…
We describe in the context of the particle physics (PP) standard model (SM) `PP-SM' the understanding of the primordial properties and composition of the Universe in the temperature range $130\GeV>T>20\keV$. The Universe evolution is…
A fundamental question of physics is what ultimately happens to matter as it is heated or compressed. In the realm of very high temperature and density the fundamental degrees of freedom of the strong interaction, quarks and gluons, come…
Appropriate combinations of up to fourth order cumulants of net strangeness fluctuations and their correlations with net baryon number and electric charge fluctuations, obtained from lattice QCD calculations, have been used to probe the…
The properties of elementary particles and their interactions at different stages of the evolution of the Universe, starting with the Planck energy $ 10 ^{19} $ GeV, are presented. We assume that the Standard Model gauge group becomes…
The quark gluon plasma is a novel state of matter in which quarks are no longer confined to bound states such as baryons and mesons. the freezing of quarkvgluon deconfined degrees of freedom is the essential ingredient in determining the…
The effect of a sharp front separating the quark-gluon plasma phase from the hadronic phase is investigated. Energy-momentum conservation and baryon number conservation constrain the possible temperature jump across the front. If one…
Heavy quarks (charm and bottoms) are one of the few probes which are sensitive to the degrees of freedom of a Quark Gluon Plasma (QGP), which cannot be revealed by lattice gauge calculations in equilibrium. Due to the rapid expansion of the…
When the phase transition from the hadronic matter to the deconfined quark-gluon plasma or quark-gluon liquid is reached, the color degrees of freedom become important and appear explicitly in the equation of state. Under the extreme…
We emphasize that a knowledge of energy and entropy densities of quark gluon plasma - a thermalized de-confined matter, formed in relativistic heavy ion collisions fixes the formation temperature and the product of gluon fugacity and…