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The critical role of shear in gravitational collapse

Pankaj S. Joshi·Rituparno Goswami·Naresh Dadhich
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Abstract

We investigate here how the shearing effects present within a collapsing matter cloud influence the outcome of gravitational collapse in terms of formation of either a black hole or a naked singularity as the final end state. For collapse of practically all physically reasonable matter fields, we prove that it would always end up in a black hole if it is either shear-free or has homogeneous density. Thus it follows that whenever a naked singularity forms as end product, the collapsing cloud must necessarily be shearing with inhomogeneous density. Our consideration brings out the physical forces at work which could cause a naked singularity to result as collapse end state, rather than a black hole.

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Pankaj S. Joshi, Rituparno Goswami, Naresh Dadhich. 2004-01-13. The critical role of shear in gravitational collapse. https://arxiv.org/abs/gr-qc/0308012

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