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arXiv · 2202.12686

Dark Energy Stars in Tolman-Kuchowicz spacetime in the context of Einstein Gravity

Piyali Bhar
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Abstract

Dark energy is the component in the present Universe with the greatest abundance, and it is responsible for the accelerating expansion of the Universe. As a result, dark energy is likely to interact with any compact astrophysical object [Muhammad F.A.R. Sakti and Anto Sulaksono, {\it Phys. Rev. D} {\bf 103}, 084042 (2021)]. In present paper, we propose a model for a dark energy star made up of dark and ordinary matter in which the density of dark energy is proportional to the density of isotropic perfect fluid matter. In the context of general relativity, the model is derived in the curved Tolman-Kuchowicz spacetime geometry [Tolman, Phys Rev 55:364, (1939); Kuchowicz, Acta Phys Pol 33:541, (1968)]. Here, we look at how dark energy affects stellar mass, compactness, and equilibrium etc. The physical parameters of the model e.g., pressure, density, mass function, surface redshift etc. are investigated, and the stability of stellar configuration is studied in detail. The model has interesting properties because it meets all energy criteria and is free from central singularities. The maximum allowable mass has been obtained from our model with the help of $M-R$ diagram. We analyse many physical properties of the model and checked that it meets all regularity constraints, is stable, and therefore physically realistic.

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Piyali Bhar. 2022-02-24. Dark Energy Stars in Tolman-Kuchowicz spacetime in the context of Einstein Gravity. https://doi.org/10.1016/j.dark.2021.100879

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