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arXiv · 2105.06297

Cosmological Evolution via Interacting/Non-Interacting Holographic Dark Energy Model for Curved FLRW Space-time in Rastall Gravity

Abstract

In this work, we explore the phenomenon of cosmic evolution using curved FLRW space-time bounded by apparent horizon with a specific holographic cut-off. To this end, we use the framework of Rastall gravity (RG) and universe is assumed to be consists of interacting/ non-interacting dark energy (DE) and dark matter (DM). In both scenarios, we evaluate exact solutions of the dynamical equations and constraint the holographic parameter $c^{2}(z)$ assuming a slowly varying function of red-shift during non-interacting model. For interacting model, we consider $c^{2}$ as a constant function of red-shift. Moreover, we analyze nature of the obtained results via deceleration parameter $(q)$, statefinder pair $(j,s)$ and $Om(z)$-diagnostic by constraining the involved model parameters using latest observational data. The graphical analysis showed that interacting model is very close to $\Lambda$ cold DM ($\Lambda$CDM) model as compared to non-interacting case. We conclude that this holographic proposal is enough to describe the cosmic evolution at an accelerating rate.

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BibTeXRIS

Rabia Saleem, Shahnila. 2021-05-12. Cosmological Evolution via Interacting/Non-Interacting Holographic Dark Energy Model for Curved FLRW Space-time in Rastall Gravity. https://arxiv.org/abs/2105.06297

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