What is the primary reason active nuclear fusion ceases in a white dwarf?

Answer

The pressure supporting it is not dependent on temperature.

Unlike main-sequence stars where cooling causes pressure drop and reignition, electron degeneracy pressure remains stable even if the core temperature plummets, locking the nuclei configuration and preventing the heat required for fusion.

What is the primary reason active nuclear fusion ceases in a white dwarf?

#Videos

Why Don't White Dwarfs Fuse Their Carbon and Oxygen? - YouTube

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