How compact is the core now? The mass of the core divided by zero diameter is infinity. Anything divided by zero is infinity, and that is where our understanding of mathematics and physics stops. Our science and math don't know how to cope with infinities in equations. In other words, we don't have the mathematical tools to think about such a strange state of matter. Our understanding of physics ends here. However, our physics and math work fine just outside the singularity.
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