Effect of Interacting Dark Energy on Expansion of the Universe

Debasis Sahu; Bibekananda Nayak

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arXiv · 1912.12000

Effect of Interacting Dark Energy on Expansion of the Universe

Debasis Sahu·Bibekananda Nayak

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Abstract

In our present work, we study the evolution of the universe by assuming an interacting dark energy model, where dark energy interacts with matter. Basing on this model, first we calculated the dark energy density parameter and using this we have picturised the expansion of the universe. From our analysis, we found that presently observed accelerated expansion of the universe can be explained by interacting model, if the dark energy is quintessence type. Though equation of sate parameter of dark energy $\gamma_{\phi}$ for quintessence varies between $0$ and $-1$, our results predict that accelearted expansion is only possible for $\gamma_{\phi}$ less (more negative) than $-0.166$. It is also found that in early time the universe was undergoing an decelerated phase of expansion and transition from deceleration to acceleration would occur in recent past. Further, our model predicts that in near future again expansion of the universe will undergo a second transition from accelerated phase to a decelerated one and finally decelaration parameter will take a constant positive value $1/2$ as early universe indicating a constant rate of deceleration in far future like distant past.

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Debasis Sahu, Bibekananda Nayak. 2019-12-27. Effect of Interacting Dark Energy on Expansion of the Universe. https://arxiv.org/abs/1912.12000

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