Modelling of a Binary System with a Quadratic Equation of State

This study investigates Einstein-Maxwell field equations with anisotropic pressure by means of a quadratic equation of state (Bose-Einstein equation of state) in the presence of an electric field and a modified version of the metric potential proposed for Korkina and Orlyanskii (1991). We obtain new classes of models that satisfy all the physical conditions for a realistic star. According to visual analysis, physical properties including energy density, radial pressure, charge density, and anisotropy are consistent with the stellar binary system GW191219, which is composed of a neutron star and a black hole.