What is the edge of the universe like? Is it a brick wall or what? Will we be able to go past our universe someday?

Too bad it's not a brick wall or something like that. Actually, there really is no "edge" of the universe so we can't go past it. There are two cases that could happen. One is that the universe will expand forever. This means that the universe is infinite in size so it doesn't have an end. It just goes on and on and on. The second case is that the universe will end in a Big Crunch. In this case the universe is finite in size because of gravity.

So if it's finite in size, why isn't there an edge we can go to? That's because of a weird little thing gravity does to space--it curves it!

Einstein first came up with the idea of gravity curving space. That's how the Earth orbits the sun. It wants to go straight but the Sun curves the space around it so the Earth can't go flying off.

There is so much matter in the universe that space is bent back on itself! It's sort of like how you can bend a wire until its ends touch, you come up with a circle. You can walk around a circle forever without coming to an edge.

So, the universe can be finite but have no edge. It's similar to the Earth. The Earth has a finite surface area but it doesn't have an edge that you can fall off (lucky for Columbus...)

Submitted by Lance (age 13, Utah, USA)
Submitted by Brent (age 9, Tenessee, USA)
Submitted by Alyssa (age 12, California, USA)
(August 21, 1997)

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Last modified prior to September, 2000 by the Windows Team

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