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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. In reality there is no "edge" of the universe so we can't go past it. There are two cases depending on the mass of the universe. One is that the universe will expand forever. This means that the universe is infinite in size and therefore doesn't have an end. 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.

Einstein first theorized that space is bent by gravity in his theory of relativity. If there is enough mass in the universe then space will be bent so much that it will bend back on itself. It's like if you bend a wire back on itself (until the ends touch), you get a circle.

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

Submitted by Lance (Utah, USA)
Submitted by Brent (Tenessee, USA)
Submitted by Alyssa (California, USA)
(August 21, 1997)



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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA