The nature of the naked singularity in generalized Vaidya spacetime and white hole geodesics




generalized Vaidya spacetime, naked singularity, geodesics, matching, white hole geodesics, black hole


This paper gives conditions to the energy-momentum tensor when the gravitational collapse of generalized Vaidya spacetime results in a naked singularity. We also consider the gravitational collapse of a matter cloud whose interior is described with Vaydia-de Sitter spacetime—when the collapse ends, this metric must be the de Sitter one, and the result of such a collapse is a so-called regular black hole. We provide the geodesic equations for the case when the matter is described with the equation of the state both P = −ρ and P = αρ, where α belongs to the interval (0,1/3]. We match these geodesics with geodesics in the Schwarzschild metric. We also explain the nature of white hole geodesics with either the naked singularity formation or the regular black hole formation.


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Theoretical Physics