Sculpting space-time itself
The idea that, by harnessing very high gravitational fields, the form of space-time itself could be sculpted, and possibly formed into loops that no longer interfaced with our physical universe.
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What is space-time curvature?
Imagine if your entire existence was confined to a two-dimensional sheet. The only directions you can move in, look in, even know about are along this sheet; there is no 'up' or 'down'. Imagine now that you are equipped with a lit candle, or its two-dimensional equivalent, anyway! The light from the candle travels outwards from the candle in all directions across the sheet, illuminating you in the process.
Now, if the sheet is perfectly flat in the third dimension, the one you are unaware of, the light will continue to travel outwards forever, you will never see it again. But what if the sheet is curved in the third dimension?
If instead of being flat, the sheet is wrapped around a ball, then the light from your candle will not move forever outwards. Confined to the surface of the ball, it will eventually come back around to where it started. This includes the light reflected off of you. The time it takes to come back will depend on the size of the ball. Let's assume that the ball is small enough that if you marked a spot on the sheet, then walked in a straight line, you would return to that mark in twenty steps. In this case, if you looked straight ahead, you would see the back of yourself standing twenty paces in front of you. If you looked to the left, you would see your right side twenty paces away. Similarly for any direction you care to look; and if you could look past those images, you would see yourself another twenty paces beyond.
Another crazy consequence of this is if you start drawing circles around yourself, each one bigger than the last, you'll eventually be standing outside of a very small circle. If this doesn't make sense, grab a ball, orange or globe and do the test!
If your brain isn't hurting enough already, imagine the scenario if the sheet was wrapped around a football, or a donut. Try tracing straight lines across these surfaces and imagine what you might see if you looked in those directions. Remember that the light might not have to travel so far to get back to you in some directions, so this might alter your perceptions of time and simultaneity...
If that's not enough to break you, then ease your way back into the third dimension. What if the universe is curved in a fourth dimension we can't perceive? If our space is wrapped around a four-dimensional equivalent of a ball...we should eventually encounter ourselves in all directions, right? Additionally, what happens if you draw spherical shells around yourself, each time increasing the diameter?
This concept I have been ranting about is known as space-time curvature.
Curving space-time
We know that space-time bends around high gravitational fields, for example, in the vicinity of a black hole. Now consider the possibility that, by harnessing such sources of high gravity, space-time could be pinched off, caused only to point back on itself, and thus form a loop or sphere. In such a region of space-time, the only potential movements would lead to other points within that same space-time loop, thus a region of space-time has been created which no longer exists within our physical universe.
Questions
What might be the experience of being trapped within such a space-time loop?
How about different sized areas? Loops of several light years circumference?
Related concepts
See also
Swear: a worm game played on a variety of curved surfaces - much like the analogies above. It might help you wrap your head around this stuff, plus it's fun! For Windows, Linux and Mac OS X.
