**Ask a monkey a physics question thread**

[MadMojoMonkey]

This interests me a great deal. I'm not convinced it's 100% true. For example, let's say you're inside a black hole, and it nearly collides with another. Can you know there is another black hole beyond your event horizon? Well, actually, yes, I think so, because each black hole effects the spin of the other.

Again, I can not speculate on what might be inside a black hole, there is simply no data. There is strong reason to believe that no data will ever be available.

The event horizon is a boundary, inside which the gravitational pull is so vast that not even photons can escape. A photon experiences a red shift as it leaves a gravity well. Since it can not trade velocity to pay the energy toll of escaping the gravity well, it pays with it's frequency. The depth of the gravitational well at the event horizon is such that a photon would experience an infinite red shift, giving up ALL of it's energy in the form of added entropy to the system.

Photons, the fastest, least massive particles in the universe can not escape, so what can be "seen" inside it? Something must cross the boundary, in order to be observed, AND it must carry some information from the other side that is not lost in crossing the boundary.

This is how black holes slowly lose their energy, according to my understanding (which may well be very flawed) of Hawkins' ideas. If you can see that your black hole is losing x amount of spin at x rate, you might be able to determine that your black hole is close to another black hole.

Of course, I have no idea if this is true. It's just my interpretation of Hawkins' ideas. But it demonstrates, to me, that the concept we cannot observe beyond an event horizon is perhaps flawed.

Hawking radiation is a strange beast indeed. It is NOT the result of a particle crossing an event horizon from the inside, though. Hawking radiation is a result of space being not empty, but merely the ground state of the sum of all the probabilities of all the possible things that could be there. If enough energy is poured into a finite region of space, particle anti-particle pairs may erupt and annihilate spontaneously (provided all conservation laws are followed, and noting E^2 = p^2c^2 + m^2c^4). They may decay into other particles before they annihilate, and if something strange happens, they may become separated and never annihilate after all.

This final case is what Hawking radiation is. Near the event horizon (like within billionth's of an inch), there is an intense gravitational field. There is an immense amount of gravitational energy. If enough of it sloshes close together, there will be particle anti-particle pairs created. One member of the pair may fall into the event horizon, while the other escapes. In this way, the black hole ejects particles. However, none of the particles that are ejected actually came from inside the event horizon.