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تسجيل مستخدم جديدAnisotropic compact stars in the mimetic gravitational theory
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تأليف
G.G.L. Nashed
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In this paper, we consider the mimetic gravitational theory to derive a novel category of anisotropic star models. To end and to put the resulting differential equations into a closed system, the form of the metric potential $g_{rr}$ as used by Tolman (Tolman 1939) is assumed as well as a linear form of the equation-of-state. The resulting energy-momentum components, energy-density, and radial and tangential pressures contain five constants; three of these are determined through the junction condition, matching the interior with the exterior Schwarzschild solution the fourth is constrained by the vanishing of the radial pressure on the boundary and the fifth is constrained by a real compact star. The physical acceptability of our model is tested using the data of the pulsar 4U 1820-30. The stability of this model is evaluated using the Tolman-Oppenheimer-Volkoff equation and the adiabatic index and it is shown to be stable. Finally, our model is challenged with other compact stars demonstrating that it is consistent with those stars.
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