If all matter, including light doesn't leave a black hole then how does the radiation, which leads to its eventual dissipation, escape the event horizen?

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I am forever striving for increased perfection of my understanding of this world we live in. My quest through life is knowledge and I am but a child on this ubiquitous journey, as are we all. Knowledge, like the universe, is infinite.

The way I understand it is the radiation is from matter falling inward just outside of the event horizon, the intense gravity and pressure on matter gives off radiation.

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I think Sphinx is talking about Hawking radiation, which transports energy from inside the black hole's event horizon, causing it to evaporate.

One version of the explanation for this is to consider virtual particle/antiparticle pairs, which are constantly popping into existence and then annihilating again, throughout what we would think of as empty space. They are "virtual" particles because the energy of their existence is merely borrowed (as they spring into existence) and repaid (as they annihilate), all within a space of time allowed by Heisenberg's Uncertainty Principle. So their life-span falls below the sensitivity of the Universe's energy book-keeping, because they exist for such a short period of time.
In the vicinity of the black hole's event horizon, however, virtual pairs may become separated by the black hole's gravity: one falls into the hole, the other escapes. They never reannihilate, and so they've become real particles.
Where does the energy come from to allow them to persist? From the black hole's gravitational energy. In effect, the particle that falls into the hole contributes negative energy to it, while the other particle escapes with positive energy. The black hole loses energy to the Universe, and so evaporates.

Grant Hutchison

I was thinking about something completely different.

Great explanation BTW hutch.

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Beautiful explanation which brings up two more questions because my friend, who I just recently met and directed to UniverseToday, was trying to explain this to me and was talking about positive and negative energy but he's a little eccentric and hard to understand sometimes. What is this + and - energy? I wasn't aware that there could be a negative potential to do work.

__________________
I am forever striving for increased perfection of my understanding of this world we live in. My quest through life is knowledge and I am but a child on this ubiquitous journey, as are we all. Knowledge, like the universe, is infinite.

It's a book-keeping thing. By removing energy from the black hole's gravitational field, the particles subtract from its ability to do work in the future by, say, accelerating other objects. By acquiring the particle that falls through its event horizon, the black hole has lost energy equivalent to the particle that departs from its event horizon.

Grant Hutchison

Another way of following the book-keeping: the black hole has "paid", energetically speaking, for the creation of two particles, but has only "taken delivery" of one. Once you allow for this payment up front, you don't need to apply negative value to one of the particles.

Grant Hutchison

okay, so it's just like every other scientific term out there and is a description of the action taking place. It's not a "negative potential to do work," it's a subtraction of the overall energy sustained within the blackhole which diminishes the black hole's "potential to do work" a.k.a. energy in it's entirety. Negative energy is the subtraction of energy from something as a result of quantum physics?

__________________
I am forever striving for increased perfection of my understanding of this world we live in. My quest through life is knowledge and I am but a child on this ubiquitous journey, as are we all. Knowledge, like the universe, is infinite.

The way I saw it was that there was, for a short time, actual negative energy going in when the particles were separated and unable to collide. Negative energy can exist for a short time under the heisenburg uncertainty principle. Like for squeezed light. Of course no known process is known to separate the negative energy portion of the squeezed light from the positive energy portion.

Of course, then there's this paradox: If there was a highly spinning portion of space, such that when two things entered one right after the other, they would be spun such that they were going practically side by side and moving roughly parallel to one another, what would happen if squeezed light entered?

Something tells me that the answer to this is that a highly spinning portion of space contains real energy, or would break the squeezed state, or something like that. Either that, or maybe it IS possible to separate positive energy from negative energy. :P