Why have no theoretical, non-radiating black dwarfs been observed in the universe yet?

Answer

The universe is not old enough for them to have cooled sufficiently

Since the universe is approximately 13.8 billion years old, isolated white dwarfs have not had enough time to radiate away all their stored heat and cool down to become theoretical black dwarfs.

Why have no theoretical, non-radiating black dwarfs been observed in the universe yet?

#Videos

Are white dwarfs stars -- a debate! - YouTube

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