What is a Black Hole Made of?
Question: I googled this question while looking for an answer to something even more vague: what is a black hole made of? If the 3 observable properties or a black hole are supposed to be mass, charge, and angular momentum, then what “inside” the black hole can still provide those properties if all matter in a black hole has supposedly been destroyed? The only thing I’ve been able to imagine is that a black hole does not actually destroy any matter that falls into it … it just prevents us from observing it. Otherwise the implication is that mass, charge, and angular momentum can exist independently of matter. — Rob
Answer: As you already know, black holes are places where extreme gravitational attraction draws everything, even light, to a single point in space. The problem with understanding exactly what happens to the stuff that pulled into a black hole is that physicists really don’t have a complete understanding of how gravity works under the extreme conditions found in a black hole. Called “quantum gravity”, an understanding of how gravity works in a black hole requires physicists to figure out what happens to gravity at atomic-scale levels. The physical properties of a black hole, which as you have said are mass, charge, and angular momentum, are measurable and are properties that derive from the event horizon of the black hole. Inside the event horizon, which is where quantum gravity effects start to come into play, are poorly understood. In the end, your suggestion that matter is not “destroyed” when it enters a black hole but just becomes unobservable to us, is plausible. Physicists cannot be definitive on this issue, though, as we just don’t have a good understanding of how gravity works at the center of a black hole.
Jeff Mangum