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تسجيل مستخدم جديدEquation of State for Cosmological Matter at and beyond QCD and Electroweak Eras
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تأليف
Abdel Nasser Tawfik
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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, that allows us to consider the 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, $p/rhosimeq 0.2$, 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. The combined equation of state can be used for modeling the expansion of the Universe from very early times and through the EW and QCD era.
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I review recent developments in the studies of the phase structure and equation of state in finite temperature QCD on the lattice.
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