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arXiv · 1803.09247

Qualitative behavior of cosmological models combining various matter fields

Parth Shah·Gauranga C. Samanta·Salvatore Capozziello
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Abstract

The late time accelerated expansion of the universe can be realized using scalar fields with given self-interacting potentials. Here we consider a straightforward approach where a three cosmic fluid mixture is assumed. The fluids are standard matter perfect fluid, dark matter, and a scalar field with the role of dark energy. A dynamical system analysis is developed in this context. A central role is played by the equation of state $\omega_{eff}$ which determines the acceleration phase of the models. Determining the domination of a particular fluid at certain stages of the universe history by stability analysis allows, in principle, to establish the succession of the various cosmological eras.

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Parth Shah, Gauranga C. Samanta, Salvatore Capozziello. 2018-03-25. Qualitative behavior of cosmological models combining various matter fields. https://doi.org/10.1142/s0217751x18501166

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