The Role of Quark-Gluon Plasma in the Early Universe

Year 2018, Volume: 1 Issue: 2, 52 - 68, 21.01.2019

Gaber Faisel Sami Khalaf

Abstract

In an era of the early Universe at a time estimated to be a
millionth of a second after the Big Bang, the Universe was filled
with quark-gluon plasma. In this plasma and due to the high
temperature the strong coupling constant, that characterizes the
magnitude of the strong force acting on quarks and gluons, becomes
so small. As a consequence quarks and gluons inside this plasma
can be considered as an ideal gas of gluons and massless quarks
that weakly interact with each others. Thus, for this plasma, one
can describe its characteristics by the equations of states that
relate both energy density and pressure to its temperature. This
has been done in several models in the literature with the recent
information about the properties of the quark-gluon plasma
provided by relativistic heavy-ion collision experiments and some
astrophysical measurement. In this article we review three of
these models namely the MIT bag model, Model 1 and Model 2.
Moreover we solve Einstein's field equations of the general
relativity,that describe our universe, to show the time evolution
of energy density, pressure and temperature in the early universe
in these three models. This kind of study is important as our
present universe evolved from a universe filled with quark-gluon
plasma.

Keywords

Quark-Gluon Plasma

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