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Yes, the no-hair theorems are asymptotic, and yes a frozen star or red hole approach has some accuracies associated with it. However, the issue of cosmic censorship is not well understood, and is still relevant to your situation. In particular, if a collapsing system forms a singularity that is not naked, then the event horizon could introduce long range ...


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First, I worry that you might confuse a singularity, which is a region (possibly pointlike) where the curvature is undefined (or infinite), versus a black hole, which is a special surface with a particular global property in an asymptotically flat spacetime. There is a famous conjecture (the cosmic censorship conjecture) that every singularity is within an ...


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The event horizon of static black holes without charge is the same for every observer, and it is located at the Schwarzschild radius. Even for an observer falling into the black hole the event horizon is the same, but at the difference that he will not notice the presence of any event horizon when falling through it. In the meanwhile outside observers will ...


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To take your question literally, we may speak of it because our speech is not bound by nature or reality - one walk down the 'Fiction' aisle of a bookstore will demonstrate that. We write of and speak of and theorize about many things we cannot, or will not experience (such as other multiverses, interiors of stars, etc.). Why would you think we would be ...


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No, you can't send information through an event horizon with gravitational waves. When a compact body contracts to form a black hole it leaves the vacuum spacetime outside the body in a curved manner. That's because certain kinds of curvature can persist on their own, even static ones,they are called vacuum solutions, and they are curved spacetimes that ...


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Far away from a black hole, spacetime is curved only a little bit, and many different things could curve it like that out there. It's like if you had a dollar in your pocket, and it's been there for a long time, and you can't remember if you got it from your boss or from your friend. But a dollar is a dollar. So you could have a massive star, or a black ...


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Although we don't have a quantum theory of gravity, we think we have some reliable knowledge about the properties of black holes from general relativity. One thing we think we know is the so-called "No-hair conjecture", which says that black holes can be described by just three numbers: mass, charge, and angular momentum (i.e. how much they are spinning). ...


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The singularity probably does not exist, as GR likely breaks down at those size / energy scales. When we have a full quantum description of gravity we may know what's really there. By the way, the part of the black hole we fully understand is actually the vacuum solution - the Schwarzschild metric - which includes the event horizon but not the source mass. ...


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It's almost certainly incorrect that the center of a black hole is a singularity as this would be at odds with quantum mechanics. Just how exactly it looks like would be something to ask of a theory of quantum gravity! Regardless of being a singularity or not, the mass is determined by how much mass you stuff into your black hole. Hence black holes of ...


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The density of black holes isn't infinite. Some black holes have the billionfold density of our sun (like the black holes in center of galaxies). There are big and small black holes.


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It's the distance of the photon sphere in the limit. The answer is implied by the Wikipedia entry for photon sphere: "Any free fall orbit that crosses [the photon sphere] from the outside spirals into the black hole. Any orbit that crosses [the photon sphere] from the inside escapes to infinity." The Wikipedia entry implies that any orbit that crosses, from ...



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