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Journal

Equation of state for cosmological matter at and beyond QCD and electroweak eras

By
Tawfik A.N.
Mishustin I.

Various thermodynamic quantities for baryon-free matter are calculated by combining the most reliable non-perturbative and perturbative calculations, especially the most recent ones including as many quark flavors as possible. We extend these calculations by including other degrees of freedom (dof), such as photons, neutrinos, leptons, electroweak particles and Higgs bosons, which allows us to consider temperatures up to the TeV-scale. The calculations show that similar to QCD, the EW phase transition is also a crossover. We have found that while the equation of state for the hadronic matter is linear, p r 0.2, the one for higher temperatures is rather complex; it exhibits two crossover-type phase transitions, corresponding to strong and EW matter. At even larger energy densities, the deduced EoS becomes linear again and close to ideal gas. Analytical parameterizations of obtained results are presented. The combined equation of state can be used for modelling the expansion of the Universe from very early times and through the EW and QCD era. © 2019 IOP Publishing Ltd.