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arXiv · 1911.09546

Analytical model of dark energy stars

Ayan Banerjee·M. K. Jasim·Anirudh Pradhan
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Abstract

In this article we study the structure and stability of compact astrophysical objects which are ruled by the dark energy equation of state (EoS). The existence of dark energy is important for explaining the current accelerated expansion of the universe. Exact solutions to Einstein field equations (EFE) have been found by considering particularized metric potential, Finch and Skea ansatz \cite{Finch}. The obtained solutions are relevant to the explanation of compact fluid sphere. Further, we have observed at the junction interface, the interior solution is matched with the Schwarzschild's exterior vacuum solution. Based on that, we have noticed the obtained solutions are well in agreement with the observed maximum mass bound of $\approx$ 2$M_{\bigodot}$, namely, PSR J1416-2230, Vela X-1, 4U 1608-52, Her X-1 and PSR J1903+327, whose predictable masses and radii are not compatible with the standard neutron star models. Also, the stability of the stellar configuration has been discussed briefly, by considering the energy conditions, surface redshift, compactness, mass-radius relation in terms of the state parameter ($\omega$). Finally, we demonstrate that the features so obtained are physically acceptable and consistent with the observed/reported data \citep{Gondek-Rosinska,Glendenning}. Thus, the present dark energy equation of state appears talented regarding the presence of several exotic astrophysical matters.

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Ayan Banerjee, M. K. Jasim, Anirudh Pradhan. 2019-11-20. Analytical model of dark energy stars. https://doi.org/10.1142/s0217732320500716

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