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arXiv · 1205.3263

Shell-crossings in Gravitational Collapse

Pankaj S. Joshi·Ravindra V. Saraykar
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Abstract

While studying the continual gravitational collapse of a massive matter cloud in general relativity towards examining collapse final states, an important issue is that of whether shell-crossing singularities can develop as the collapse evolves. We examine this here to show that for any spherically symmetric collapse in general, there is always a finite neighborhood of the center in which there are no shell-crossings taking place. It follows that in order to study the final genuine shell-focusing singularity of collapse where the physical radius of the matter cloud shrinks to a vanishing value, we can always consider without any loss of generality a collapsing ball of a finite comoving radius in which there are no shell-crossings taking place. This clarifies an important point for gravitational collapse studies.

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Pankaj S. Joshi, Ravindra V. Saraykar. 2013-04-29. Shell-crossings in Gravitational Collapse. https://doi.org/10.1142/s0218271813500272

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