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arXiv · 2011.04649

Does emergent scenario in Ho\v{r}ava-Lifshitz Gravity demand a ghost field?

Akash Bose·Subenoy Chakraborty
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Abstract

The non-singular model of the Universe i.e. emergent scenario is now very well known in cosmology. In Einstein gravity such type of singularity free solution is possible in the context of non-equilibrium thermodynamical prescription (both in first and 2nd order theory) with particle creation mechanism. Also there are various models of emergent scenario in different gravity theories. The present work is a twofold attempt namely (i) it has been examined whether it is possible to have singularity free solution in Ho\v{r}ava-Lifshitz modified gravity theory, (ii) if such singularity free solution exists then whether such solution is thermodynamically viable. It is found that perfect fluid matter distribution with phantom nature can generate such type of solution for closed and flat model. Finally thermodynamical analysis has been studied both at the apparent horizon and at any arbitrary horizon.

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Akash Bose, Subenoy Chakraborty. 2020-11-08. Does emergent scenario in Ho\v{r}ava-Lifshitz Gravity demand a ghost field?. https://doi.org/10.1016/j.dark.2020.100740

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