- This is what you're missing: the bigger a black hole, the less "dense" it is, if by density we mean its mass divided by the cube of the radius of its event horizon.
That's because the radius of a black hole is proportional to its mass!
(All this is for nonrotating black holes, and for nonrotating black holes a better definition of "density" might be the mass divided by 4π/3 times the cube of its radius. But that doesn't affect my point; black holes in nature don't generally rotate so much as to deviate strongly from being spherical, and the Universe doesn't seem to be rotating much at all, though sometimes experiments seem to show otherwise.)
John Carlos Baez
npub1nf…3nqe4
2025-12-15 10:40:11 UTC
in reply to nevent1q…yt9e
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2025-12-15 10:40:11 UTCEvent JSON
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