Nowhere Man said:
The_Darkness said:
A degree in astrophysics, a decent knowledge of gravitational lensing (which is bent space) and a ridiculous amount of my spare time thinking about how light would travel through a 4d tunnel...
You did ask
Any thoughts on how a singularity would behave?
This is getting off-topic... but then again, Sci-Fi movies are at their best when they inspire discussion about science, so I hope no-one minds...
Anyway, what would a singularity look like? That depends.
Singularities don't actually fit into modern physics at the moment - we just know that if you get enough mass together that light itself can't escape (ie, a black hole), something very strange happens in the very middle. If we try working out exactly what is happening in the middle, you get infinities and 1/0, and... well, basically our understanding of physics breaks down at that point. A good united theory of Quantum Dynamics and General Relativity could probably give us an answer, but we don't have that yet.
However, I can tell you what a black hole would look like.
From the outside - there's a very good simulated view here. Notice how objects 'behind' the black hole appear to be duplicated and placed on either side of it, along with everything else being bent around it. When people say a black hole bends space, they're not kidding. The light is getting bent as it goes past the black hole, the black hole itself acting as a sort of giant space-time lens.
From inside the black hole:
Okay, you've just flown your spaceship past the event horizon and you are now on a one-way trip to the middle. It was nice knowing you.
However, imagine standing in your spaceship in a room with no windows and looking around. You'd still be able to tell which direction the black hole was in. If you are looking in the direction of the middle of the black hole, things will look very
very dark. As in, pitch black. That's because for you to see anything, light would have to be heading away from the black hole, and the whole point of being inside the event horizon is that it can't do that. (There might be some effects that would allow some photons to enter your eyes, but they would so few that you still wouldn't notice anything.)
Now, imagine that your spaceship has windows again. Look directly behind you. You'll see ordinary space, from outside the black hole (and anything that was foolish enough to follow you in). Interestingly, so long as you don't turn your head, if you're travelling backwards into a black hole, you won't actually see anything strange until the forces of gravity start getting ridiculously strong.
Finally, let's look to one side. So the way you came in is on your left, and the middle of the black hole (your ultimate destination) is on your right. The right hand side of your vision can't see anything (for the reasons explained above). The left hand side of your vision shows ordinary space looking more and more warped the closer it gets to the middle of your vision. So what's at the middle of your vision? Take a look here again. Notice the bright ring just around the event horizon? That's a layer of ridiculously focused light. Within the black hole, that layer will be very bright indeed, and will appear whenever you turn your head to one side.
So as it turns out, your first symptom of travelling into a black hole...?
...Would probably be sun-burn.
EDIT: Things would actually look a fair bit different if you were to travel into a rotating black hole. For starters, there are two horizons, and you could safely pass the first horizon without being doomed to travel to the heart of the black hole. Instead, you'd just be doomed to live the rest of your days in the space-time layer between the two horizons...
