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Reading The brief history of time by Stephen Hawking and the chapter 7 BLACK HOLES AIN’T SO BLACK has below.

Does it mean if his theory is correct, a black hall can disappear on its own?

Because energy cannot be created out of nothing, one of the partners in a particle/antiparticle pair will have positive energy, and the other partner negative energy. The one with negative energy is condemned to be a short-lived virtual particle because real particles always have positive energy in normal situations. It must therefore seek out its partner and annihilate with it. However, a real particle close to a massive body has less energy than if it were far away, because it would take energy to lift it far away against the gravitational attraction of the body. Normally, the energy of the particle is still positive, but the gravitational field inside a black hole is so strong that even a real particle can have negative energy there. It is therefore possible, if a black hole is present, for the virtual particle with negative energy to fall into the black hole and become a real particle or antiparticle.

The positive energy of the outgoing radiation would be balanced by a flow of negative energy particles into the black hole. By Einstein’s equation $E = mc^2$ (where $E$ is energy, $m$ is mass, and $c$ is the speed of light), energy is proportional to mass. A flow of negative energy into the black hole therefore reduces its mass. As the black hole loses mass, the area of its event horizon gets smaller, but this decrease in the entropy of the black hole is more than compensated for by the entropy of the emitted radiation, so the second law is never violated.

Moreover, the lower the mass of the black hole, the higher its temperature. So as the black hole loses mass, its temperature and rate of emission increase, so it loses mass more quickly. What happens when the mass of the black hole eventually becomes extremely small is not quite clear, but the most reasonable guess is that it would disappear completely in a tremendous final burst of emission, equivalent to the explosion of millions of H-bombs.

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We cannot be sure yet if a Black Hole fully evaporates into "nothing" or leaves a stable quantum remnant. Hawking Radiation is hard to observe because it is an incredibly slow process for larger black holes, because they are "cold" (have black body temperatures billionths of a degree above absolute zero) and lose energy at a very slow rate. Some experimental analogues exist however: Is there any experimental evidence for Hawking radiation?

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Hmm, according to the excerpt, it says that Black Holes would end up with an explosion of trillion Hydrogen bombs. But now the thing is, has anyone seen a black hole ending up yet? The answer is no. But yes it will end up on it's own because no thing in the universe creates energy on it's own from no where. So, if it's releasing energy it will be exhausted. The only thing is it will take a long time before it goes down it's own

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