What You See . . .(For the sake of description, this black hole will have two event horizons.) As I drift closer and closer to the outer event horizon, you notice something strange - as I wave to you, my hand starts slowing down gradually. The shiny white space suit loses its shininess. I keep on getting slower and slower and dimmer and dimmer as I move toward the center of the black hole. This goes back to Einstein's theory about the nature of gravity and spacetime. The black hole's mass is so huge that it warps spacetime a great deal, and you are seeing the effect of a curvature in spacetime. That's why I seem to be moving slower. It's called time dilation. I'm getting dimmer because of something called redshifting. This is similar to the Doppler effect with sound, except that it affects light waves. As I move away from you and enter severely curved spacetime, the frequencies of the light waves that bounce off of me and reach your eyes become longer and longer, until right near the event horizon when you'll need to whip out the Infrared Telescope to see me. At the exact moment I hit the event horizon, it appears to you as though I have stopped completely. This is because time at this point is infinitely curved (it flips with space, remember?) and it will take an infinite amount of time for you to see me pass through the event horizon. |
|
What I See . . .Whereas you see me moving slower, I see you start to move faster. I can't feel the change in time because everything around me is affected by it, too. What I do notice, however, is that the whole universe seems to be getting smaller. The view that I have of the stars and the spaceship starts to shrink. This is because of something called a light cone. A light cone is basically all the angles at which light can escape from a body of mass. As I get closer to the singularity, the light cone gets smaller. When I cross the event horizon, the light cone disappears. Space and time flip at the first event horizon, and the singularity becomes a point in my future which I cannot avoid. But since this black hole has two horizons, space and time flip back to their normal settings when I cross the point in time which is the second horizon. Now the singularity is theoretically avoidable as a place in space. As I move toward it, I see an oval window, but what I see inside it is subject to speculation. Maybe I see a bunch of stars from a different point in the galaxy; maybe I see a bunch of stars from a different galaxy altogether. Either way, it's the tidal forces I should really be worrying about. This part wouldn't be pleasant if this weren't a virtual tour. Tidal forces are, strangely enough, the same forces which cause tides on Earth. They are basically gravitational forces applied on a larger object (ie. Earth's oceans and me), with the smaller object as the source (ie. the Moon and the singularity). The general effect it would have would be that my feet would be attracted more strongly than my head, so I would be stretched out. That's the unpleasant part. But now, we've come to the end of our Virtual Tour! Thanks for joining us! | |
