Been reading A Brief History of Time, and I have a few questions I want to sort out.
Hawking talks about the event horizon and says a few things that I think I've read right:
1. The event horizon is a set of events that it is impossible to escape to a large distance from.
2. The event horizon forms the boundary of the black hole, and is formed by the rays of light that nearly escape the black hole, but not quite.
3. These light rays must be parallel, otherwise they would eventually touch and cause each other to fall into the black hole.
4. Due to the way time works within a black hole, this cannot happen as then they wouldn't be able to be at the event horizon.
5. This means that the event horizon can never decrease in area, or else the light rays would cease to be parallel and would eventually touch etc.
But then they discovered Hawking radiation. So the event horizon can decrease in size (presumably with the black hole), and indeed can decrease to 0.
I understand that this proves Hawking wrong on the nondecreasing nature of the event horizon, but what about the parallel light rays? If the event horizon does decrease in area, do the light rays touch, then fall into the black hole, though that apparently can't happen? I'd really appreciate it if someone could clear this up. Thanks
