Do bigger black holes have the same density as small black holes but are just greater in volume?
In: Physics
For a non rotating black hole, the radius R of the event horizon and the mass are proportional, but the volume grows as R^3, so the density is proportional to R^-2, meaning small black holes are denser than large black holes.
A black hole is a state of matter where there is no intra-molecular force or pressure we know of that keeps matter from collapsing onto itself. The density that relativity predicts therefore would be infinite. Since no information can escape the event horizon (where the escape velocity is greater than the speed of light) there is no way to make observations of any density of matter within, we can only probe other aspects of the nature of matter to infer.
Thing with this is that we don’t know (and likely will never know), just make assumptions based on what we know about physics in general. And black holes are sort of thing where physics turns into something quite alien to us.
Getting to some data out of a black hole for real would solve centuries worth of physics questions.
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