Viscous quark‐gluon plasma in the early universe

  title={Viscous quark‐gluon plasma in the early universe},
  author={A. Tawfik and Mohamed Wahba and H. Mansour and Tiberiu Harko},
  journal={Annalen der Physik},
In the present work a study is given for the evolution of a flat, isotropic and homogeneous Universe, which is filled with a causal bulk viscous cosmological fluid. We describe the viscous properties by an ultra‐relativistic equation of state, and bulk viscosity coefficient obtained from recent lattice QCD calculations. The basic equation for the Hubble parameter is derived by using the energy equation obtained from the assumption of the covariant conservation of the energy‐momentum tensor of… 

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