Gravitational Collapse of Bose-Einstein condensate dark matter in Generalized Vaidya spacetime

Prabir Rudra

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arXiv · 2411.02031

Gravitational Collapse of Bose-Einstein condensate dark matter in Generalized Vaidya spacetime

Prabir Rudra

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Abstract

In this work, we study the gravitational collapse procedure in generalized Vaidya spacetime with Bose-Einstein condensate dark matter density profile. We use the generalized Vaidya metric to simulate the spacetime of a big star and subsequently obtain the field equations. Then we proceed to determine the star system's mass parameter by solving the field equations. Then the gravitational collapse mechanism is investigated using the derived solutions. Investigating the nature of the singularity (if formed) as the end state of the collapse is the main goal. Dark matter in the form of Bose-Einstein condensate is expected to play a crucial role in the fate of the collapse. We see that there is a possibility of the formation of both black holes and naked singularities as the end state of the collapse depending upon the initial conditions. The junction conditions are derived with a Vaidya exterior and a Friedmann interior and some important insights are obtained. A Penrose diagram showing the causal relations between the spacetimes is generated and studied in detail.

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Prabir Rudra. 2024-11-04. Gravitational Collapse of Bose-Einstein condensate dark matter in Generalized Vaidya spacetime. https://arxiv.org/abs/2411.02031

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