## Imagining 4D

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### Imagining 4D

How do we know what 4D objects look like? I mean, I know that it's all therory, but how did the unfolded tesseract come to look like an inverted double cross?
blazes816

### Re: Imagining 4D

blazes816 wrote:how did the unfolded tesseract come to look like an inverted double cross?

Check out the animations at this site to get a better idea of this: http://www.math.union.edu/~dpvc/math/4D/folding/welcome.html

Hugh
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Okay. I'm starting to understand. Still a bit confused on how to imagin it looking in 4D, but now I at least understand how they got to what it looks like. But here's another qeustion, I havn't seen the 3D projection of a glome, but how would they get to what it looks like? Seeing as if you extend a sphere to the 4D, the same way you extend a circle into 3D, you'd just end up with a sphere....?
blazes816

That's right. Use the word "extend" carefully though, there is another operation defined by "extrusion" that gives, for example, the cylinder from the circle.
"God does not play dice." -- Albert Einstein, early 1900's.
"Not only does God play dice, but... he sometimes throws them where we cannot see them." -- Stephen Hawking, late 1900's.
moonlord
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Go here, but it only shows it unfolded. http://tetraspace.alkaline.org/forum/vi ... php?t=587&
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papernuke
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