Approximately how quickly does the core collapse catastrophically after fusion stops providing outward pressure?

Answer

In a matter of milliseconds

Once fusion ceases to generate the necessary outward thermal pressure against gravity, the core collapses catastrophically in an extremely rapid event occurring in a matter of milliseconds.

Approximately how quickly does the core collapse catastrophically after fusion stops providing outward pressure?

#Videos

High Mass Stars: Crash Course Astronomy #31 - YouTube

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