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arXiv · 1902.03617

Van der Waals Universe with Adiabatic Matter Creation

Rossen I. Ivanov·Emil M. Prodanov
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Abstract

A FRWL cosmological model with perfect fluid comprising of van der Waals gas and dust has been studied in the context of dynamical analysis of a three-component autonomous non-linear dynamical system for the particle number density $n$, the Hubble parameter $H$, and the temperature $T$. Perfect fluid isentropic particle creation at rate proportional to an integer power $α$ of $H$ has been incorporated. The existence of a global first integral allows the determination of the temperature evolution law and hence the reduction of the dynamical system to a two-component one. Special attention is paid to the cases of $α= 2$ and $α= 4$ and these are illustrated with numerical examples. The global dynamics is comprehensively studied for different choices of the values of the physical parameters of the model. Trajectories in the $(n, H)$ phase space are identified for which temporary inflationary regime exists.

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Rossen I. Ivanov, Emil M. Prodanov. 2019-02-10. Van der Waals Universe with Adiabatic Matter Creation. https://doi.org/10.1140/epjc%2Fs10052-019-6611-0

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