Compact stars and modified TOV equation in Rastall gravity

Abstract This study investigates the key characteristics of compact star configurations within the framework of Rastall’s theory of gravity, employing the Krori–Barua ansatz. By forming the field equations for a spherically symmetric line element with an isotropic matter source through Krori–Barua metric potentials, we derive the modified Tolman–Oppenheimer–Volkov equation. This equation is crucial for studying the mass–radius function, the compactness factor, and the surface redshift. Additionally, we examine various physical aspects, including energy density, pressure evolution, equation of state, adiabatic index, and stability analysis, to assess the model’s viability. Rastall’s theory, which extends general relativity by relaxing the conservation of energy and momentum, plays a central role in our analysis, particularly in understanding the enhanced stability of compact stars. Our results provide strong evidence that within Rastall’s gravitational framework, the proposed stellar structures exhibit significant stability, suggesting that this theory may offer new perspectives on the behavior of such stars.