What happens if a core remnant exceeds 3 times the mass of the Sun?
Answer
The core collapses into a singularity known as a black hole
When a remnant core has a mass significantly greater than about three times the mass of the Sun, the forces of gravity are so extreme that they overwhelm all other internal pressures, including neutron degeneracy pressure. No known force can withstand this crush, leading the core to collapse infinitely into a single point called a singularity, effectively creating a black hole.

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