Thermodynamics and statistical physics of quasiparticles within the quark-gluon plasma model

TL;DR

This paper explores how the internal structure and size variations of quasiparticles influence the thermodynamic properties of quark-gluon plasma, revealing size-dependent effects and a phase transition at high temperatures.

Contribution

It introduces a model considering quasiparticle sizes and their temperature dependence, linking quantum chromodynamics with non-Abelian Proca-Dirac-Higgs theory to analyze plasma thermodynamics.

Findings

Quasiparticle sizes increase with temperature.

Size variations affect internal energy and pressure.

A phase transition occurs when quasiparticle volume matches plasma volume.

Abstract

We consider thermodynamic properties of a quark-gluon plasma related to quasiparticles having the internal structure. For this purpose, we employ a possible analogy between quantum chromodynamics and non-Abelian Proca-Dirac-Higgs theory. The influence of characteristic sizes of the quasiparticles on such thermodynamic properties of the quark-gluon plasma like the internal energy and pressure is studied. Sizes of the quasiparticles are taken into account in the spirit of the van der Waals equation but we take into consideration that the quasiparticles have different sizes, and the average value of these sizes depends on temperature. It is shown that this results in a change in the internal energy and pressure of the quark-gluon plasma. Also, we show that, when the temperature increases, the average value of characteristic sizes of the quasiparticles increases as well. This leads to the occurrence of a phase transition at the temperature at which the volume occupied by the quasiparticles is compared with the volume occupied by the plasma.