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arXiv · 1901.03055

Gravitational Collapse in Rastall Gravity

A. H. Ziaie·H. Moradpour·S. Ghaffari
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Abstract

We study spherically symmetric gravitational collapse of a homogeneous perfect fluid in Rastall gravity. Considering a linear equation of state (EoS) for the fluid profiles, we examine the conditions under which the collapse scenario could end in a spacetime singularity. Depending on the model parameters, the singularity could be either naked or covered by a horizon. We find that a non-vanishing Rastall parameter could affect the formation of apparent horizon so that, naked singularities may form for those values of EoS parameter for which a homogeneous perfect fluid collapse in general relativity (GR) terminates at the black hole formation. Hence the visibility of the resulting singularity depends on the Rastall parameter. The solutions we obtain respect the weak energy condition (WEC) which is crucial for physical validity of the model.

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A. H. Ziaie, H. Moradpour, S. Ghaffari. 2019-01-10. Gravitational Collapse in Rastall Gravity. https://doi.org/10.1016/j.physletb.2019.04.055

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