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So lets start with the first part of your question: Black holes radiate away by the famous Hawking process. Hawking radiation has been interpreted in many ways i.e. as pair creation near the black hole, tunnelling from the black hole and almost every other physicist will have a nice way of explaining this. What is the temperature of a black hole? It ...


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Particles may be able to escape a black hole through quantum tunneling, the possibility that a particle confronted with an energy barrier it doesn't have sufficient energy to surmount, nevertheless overcomes by, in effect, tunneling through the barrier. It's a quantum mechanical effect that depends on the particle's probability function extending through ...


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This is a complicated question that opens up a lot of avenues for further discussion. I'm not sure the question as you posed it has an answer that will be helpful to you, so I'll answer a related question that might satisfy your curiosity - "Under what circumstances is it possible to remove energy from a black hole?" Remember, everything is energy, so this ...


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As far as I know, no value in the observable physical universe is infinite, but we don't know: If the universe itself is infinite or not We don't know what is inside a black hole, so I don't think there is a definite answer to your question.


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About evidence supporting the existence of Event Horizons in these very compact objects, here are some news from the well known Cygnus X-1, one of the most studied compact objects and the most promising candidate for a stellar collapse black hole: ... evidence of just such an event horizon may have been detected in 1992 using ultraviolet (UV) ...


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...why do we trust black hole physics? ... (physics which is derived by combining quantum mechanics and GR such as Hawking Radiation, things relating to the Information Paradox, etc. ) Formally, there isn't quite a reason to because we've not observed these things yet. But that's also perfectly okay as well because that is how science sometimes works: ...


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General relativity (GR) turned out to be a great mathematically beautiful theory with amazingly accurate experimental predictions/observations (e.g, bending of light, precession of Mercury, etc). This theory naturally provides some simple solutions which are called black holes. In that sense one should take them seriously as they come from a firmly ...


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At first many people didn't care much for black holes. But later people showed that they were pretty unavoidable features of the theory of general relativity and that theory made other quite precise predictions that were tested and found good. So when you are told that black holes are required if you have GR and GR looks like the best game in town then it ...


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If you correct plank units by using Einstein's Appendix 2 of "Relativity" relation meters = i c seconds, and carry the i through all equations, converting any seconds units to meters, you get better insight. For example, this gives E= -mc^2 instead of E=mc^2, which cosmology agrees with. So you also convert all mass units to negative energy units. You then ...


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A quick answer, based partially on John's comments above: Do black holes grow in size? As Rob says in his comment below, they do grow in mass, but that, in my opinion only, does not necessarily imply that they grow in size, because of the reason listed below. We don't know for sure, as we lack experimental evidence and , theoretically we are dealing with ...


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I will try and answer this in a very simple way. I think you are missing a crucial piece here. It is true that from the perspective of a remote "outside" observer (Bob) the person falling into the black hole (Alice) will never cross the horizon. However from Alice's perspective, nothing unusual will happen (in terms of laws of physics not biology, ...


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If 0celo7 didn't make sense to you: Nothing special happens to the observer that crosses the horizon (according to classical GR), he just falls in and gets crushed. It appears like someone is "stuck" to someone outside the black hole, but in a sense that are just photons that were massively delayed by the gravitational field. And this processes is very ...


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What constitutes a blackhole firewall? I think it's rather different to what you usually read about. I say this as something of a "relativist". I consider General relativity to be one of the best tested theories we've got, see Clifford M Will's paper http://arxiv.org/abs/1403.7377. However I find the given explanation of Hawking radiation unconvincing. ...



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