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Employing the quasi-Maxwell form of the Einstein field equations in the context of gravitoelectromagnetism, we introduce a general relativistic analog of Poissonâs equation as a natural outcome of the corresponding spacetime decomposition formalism. The active density introduced in this formalism, apart from the matter-energy density and pressure, includes a third component which is the gravitoelectromagnetic energy density. This general relativistic analog of Poissonâs equation is compared to another analog introduced by Ehlers et al. [Am. J. Phys. 74, 607 (2006)]. Introduction of the cosmological constant and its effect on the active mass are also discussed for both exterior and interior static spacetimes. In the stationary case, we consider the Kerr spacetime with a special choice for its interior metric.
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