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arXiv · 2211.10401

Tsallis holographic dark energy under Complex form of Quintessence model

Abstract

In this paper, we use a Tsallis holographic dark energy model in two forms, interacting and non-interacting cases, to acquire some parameters as the equation of state for the energy density of the Tsallis model in the FRW universe concerning the complex form of quintessence model. We will study the cosmology of complex quintessence by revamping the potential and investigating the scalar field dynamics. Then we analyze ($\omega-\omega'$) and stability in two cases, i.e., non-interacting and interacting. We will explore whether these cases describe a real universe by calculating fractional energy density $\Omega_{D}$ and concerning two parts of the quintessence field effect ( complex and real part ) by considering the real part of this field to be a slow-roll field. We know that the part in which the fractional energy density ($\Omega_{D} > 1$) does not describe a real universe. Also, we specified an interacting coupling parameter $b^{2}$ that depends on the constant parameter of the Tsallis holographic model ($\delta$) with respect to fractional energy density ($0.73$). Unlike independence between the fractional energy density and interacting coupling in the real quintessence model, we determine a relationship among these parameters in this theory. Finally, by plotting some figures, we specify the features of ($\omega-\omega'$) and ($\nu_{s}^{2}$) in two cases and compare the result with each other.

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BibTeXRIS

J. Sadeghi, S. Noori Gashti, T. Azizi. 2022-11-18. Tsallis holographic dark energy under Complex form of Quintessence model. https://doi.org/10.1088/1572-9494%2Faca390

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