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arXiv · 2409.18663

Tolman-Oppenheimer-Volkoff equation and static spheres in Conformal Killing gravity

Carlo Alberto Mantica·Luca Guido Molinari
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Abstract

We derive the analog of the Tolman - Oppenheimer - Volkoff equation in conformal Killing gravity in a static spherically symmetric spacetime, sourced by anisotropic fluid matter. It differs from the original equation by new dark terms associated to a conformal Killing tensor. The formulation of gravity as an Einstein equation augmented by a conserved conformal Killing tensor enables to implement the junction conditions for a sphere of anisotropic fluid with the conformal Killing vacuum. The equations are solved for a perfect fluid sphere with uniform matter density, in the Harada vacuum. The extension of Buchdahl's equation for the critical radius - mass density is obtained.

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Carlo Alberto Mantica, Luca Guido Molinari. 2024-09-27. Tolman-Oppenheimer-Volkoff equation and static spheres in Conformal Killing gravity. https://doi.org/10.1103/physrevd.111.064085

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