Frequently Asked Questions ¡V Cosmology

The Question
(Submitted December 02, 1996)
I'm a 10 year old boy who has a very hard question to ask. My teacher Mr. Sperling just had us learn about the Solar System. We just made a Internet site. Now my question. What is at the edge of the Universe ?
The Answer
That's an interesting question. The short answer is that there isn't any "edge" to the Universe, as in the edge of your school grounds where there is more property beyond. Science fiction and other dimensions aside, the best way of looking at the Universe is to think of the surface of a balloon. Right now the "balloon" is expanding (being blown up) so the distance between any two points on the balloon is increasing. However, there is no edge to the surface of the balloon. This is where cosmologists (people who study the physical nature and evolution of the Universe) and relativists (people who study Einstein's general theory of relativity) talk about a curved space-time continuum.
One observable effect of this geometry...