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arXiv · 1401.4906

QCD phase transition with a power law chameleon scalar field in the bulk

T. Golanbari·A. Mohammadi·Kh. Saaidi
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Abstract

In this work, a brane world model with a perfect fluid on brane and a scalar field on bulk has been used to study quark-hadron phase transition. The bulk scalar field has an interaction with brane matter. This interaction comes into non-conservation relation which describe an energy transfer between bulk and brane. Since quark-hadron transition curly depends on the form of evolution equations therefore modification of energy conservation equation and Friedmann equation comes into some interesting results about the time of transition. The evolution of physical quantities relevant to quantitative of early times namely energy density $\rho$ temperature $T$ and scale factor $a$ have been considered utilizing two formalisms as crossover formalism and first order phase transition formalism. The results show that the quark-hadron phase transition in occurred about nanosecond after big bang and the general behavior temperature is similar in both of two formalism.

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T. Golanbari, A. Mohammadi, Kh. Saaidi. 2014-01-20. QCD phase transition with a power law chameleon scalar field in the bulk. https://doi.org/10.1142/s0217751x1450033x

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